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kaig
08-22-2006, 02:53 PM
I'm admittedly just a homeowner, but I thought I'll see if the pros have some advice for me, and there's a potential for someone to make a little bit of money in this, too.

I bought a new home (Seacoast, NH) last year which is on a pretty sloped lot. We had some heavy rains after the (late) hydroseeding last fall, and I didn't really get much of a lawn, which made me a hobby landscaper this year -- I admire you guys doing this every day, as it's serious work, but I find it quite enjoyable, too.

Anyway, I found lawnsite in my quest to learn about lawns, stumbled upon the hardscaping forum and found a lot of real nice work here. So I decided I want to put in small retaining wall, for one because I like the looks and would like to learn how to do it (always up for something new). To justify the expense and effort, I'm telling myself it should also be helpful in dealing with the erosion problems on the slopes. Now, I'm not much of a promising customer, as, like I said, I'm in it for the experience of doing it myself, and neither could I afford spending a couple of thousand of dollars. In the pic below, the steepest slope is in the front left, about where I put in a couple of blocks just to get a feeling for how it would look (no base, no drainage etc at this time, but I will be doing it right).

In order to save expenses, I started to scrape of the existing top soil (will reuse later), and I want to just redistribute the fill (sand with bricks is what I've found so far), not bring in or haul out more stuff. However, I will obviously need the blocks, gravel, base material. If any of the NH guys here are interested in just selling me the materials (+ delivery), I might be up for that (I suppose you get stuff at a discount, so you may make a bit of money without any actual work).

And then I have a couple of questions, too, any kind of input would be appreciated.

For one, the wall is next to a patch of wooded land which was saved during the construction. However, the builder piled up fill right next to some of the trees to build up the slope, so I suspect they may be doomed anyway. I suppose by removing some of that close fill and then putting in the wall at some distance, I'm at least not going to make the situation worse?

2nd issue, on top of the hill in front of the house is the septic leach field. I'll be pretty far away from it (the wall will go only about 30' back, which is roughly where the field starts, but I'll be at the foot of the slope while the field is obviously in the flat part on top). Just want to make sure I'm not potentially overlooking any issues there?

The wall will be maybe 4' high at the highest point (front left), lower in the back, as the terrain (wooded patch) slopes up, so I don't think I have any engineering / grid issues. Does anyone know NH rules on engineering, permits, etc?

How do you guys go about designing/estimating height & materials? If it were a straight wall at given height/length, that'd be quite easy, but as I said, I want to keep the net amount of soil/fill the same, and it seems not easy for me to guess at what distance from the wooded patch the wall should be, how high, how to taper it off at the ends or turn it in, etc.? Any tips on that, or is that just what comes with your experience? I'm currently thinking I'll just form the new shape with shovel, wheelbarrow etc until it looks right to me, and then see how tall / long the wall is going to be and order materials accordingly.

I'm planning to do basically everything with handtools, which actually seems quite doable, even though it'll take quite a bit of time (but saves on the gym ;) The one thing I'm wondering about is a plate compactor, how necessary is that over handtamping? The problem is, this is going to be a weekend project which will take a while to finish, and renting a compactor a couple of times sounds quite expensive, besides I'm not really quite sure how to haul it -- I assume these things are too heavy to be moved by a single person?

Finally, though I should have asked that first, is a wall going to look good there? And is it going to help with the erosion?

XXL Hardscaper
08-22-2006, 03:30 PM
You need an Engineer......what you have there is already wrong

Walls are not meant for erosion control!

you have no footer.....you have no courses of block in the ground.

A 4 foot wall with that slope at the top and fill dirt at the toe needs to be designed by an engineer!!!!!

You need soil tests, global stability test, gravel for the footer ( yes compacted with a plate or jumpinjack ), drainage gravel, drain pipe, geo grid, filter frabric and a set of stamped drawings.

The only thing I see is alot of bad soil and some block

kaig
08-22-2006, 04:00 PM
You need an Engineer......what you have there is already wrong

Walls are not meant for erosion control!

you have no footer.....you have no courses of block in the ground.

A 4 foot wall with that slope at the top and fill dirt at the toe needs to be designed by an engineer!!!!!

You need soil tests, global stability test, gravel for the footer ( yes compacted with a plate or jumpinjack ), drainage gravel, drain pipe, geo grid, filter frabric and a set of stamped drawings.

The only thing I see is alot of bad soil and some block

Alright, thanks for the reply, I hope you're willing to get into more detail, though.

Why do you say walls are not meant for erosion control? They obviously allow for less sloped soil areas, thus less run-off / washout. I mean, imagine I built this whole thing up 7' so that the top and bottom were exactly level. That would fix pretty much all erosion, wouldn't it? (Not that I'm intending to do that, I just want to lessen the slope to what it's further back, where the current slope seems to be holding just fine even though the grass on it is still spare, too).

I know I have no footer -- I actually do have a half a block in the ground, but that's really irrelevant, as I wrote above, I just put these blocks there to get a feel for what it would look like. I didn't fill the cores either, nor are they in their final position at all. I'm going to put a base (on top of undisturbed soil) on fabric. I'm going to put drainage stone in the cores and behind the blocks. I'm not sure I'm going to do a drainage pipe -- according to the manufacturer it's not needed for this size wall, but I may do it anyway.

Since I'm moving the fill I'm cutting out in front of the wall behind it, the slope behind the wall will actually be level for a couple of feet. Besides, even for a slope behind the wall, the manufacturer allows for a 5 ft wall without geogrid (for sandy soil, which I have, besides the bricks in it, but I don't think they're particularly destabilizing at all). I believe that's a good idea for drainage -- otherwise, the run-off from the area above would just collect right behind the wall caps with no place to go. By having a few feet behind the wall level, it'll still pool there, but more spread out and it will have a larger area to percolate through. Does that make sense?

So, you guys would feel uncomfortable to build this kind of wall without an engineer's approval? Again, I'm just looking to ease the slope, not eliminate completely, it's not a very tall wall at 4' in the front and ~ 2' in the back.

DVS Hardscaper
08-22-2006, 04:06 PM
Walls are not meant for erosion control!


U sure bout that?????

Absolutely walls can be used as a form of erosion control.



Mr. Homeowner - your best bet is to contract with a competent, experienced professional. Check their references, visit their jobs, and go back 3-5 years with their jobs/references. New jobs always look nice....

XXL Hardscaper
08-22-2006, 07:36 PM
DVS you apparently do not deal with many civil or geo technical engineers, I on the other hand I do. I called my Uncle who designs the walls that I have built before I responded to what you said. Erosion control and water remediation is not there design, it may be an indirect result of the wall but not the reason. If an engineer is contacted for erosion control they will never spec a wall to take care of that issue. What I gave was sound advise, CALL AN ENGINEER. Do not start with a contractor , I don't care what there experience is, It will cost you less in the long run.

Mr. Homeowner as you refer to him wants to build this himself DVS Hardscraper, so the advise and things I mentioned are sound. The advise you gave was flawed, never mind you didn't even give any advise to his wants and needs..........Typical :laugh:

Mike33
08-22-2006, 10:20 PM
Please feel free to check out my site www.bobcatservice33.com and contact me if you wish.
Mike

Mike33
08-22-2006, 10:32 PM
DVS you apparently do not deal with many civil or geo technical engineers, I on the other hand I do. I called my Uncle who designs the walls that I have built before I responded to what you said. Erosion control and water remediation is not there design, it may be an indirect result of the wall but not the reason. If an engineer is contacted for erosion control they will never spec a wall to take care of that issue. What I gave was sound advise, CALL AN ENGINEER. Do not start with a contractor , I don't care what there experience is, It will cost you less in the long run.

Mr. Homeowner as you refer to him wants to build this himself DVS Hardscraper, so the advise and things I mentioned are sound. The advise you gave was flawed, never mind you didn't even give any advise to his wants and needs..........Typical :laugh:
I think he was just stacking them to see what they look like, i have done that for customers at times when im bidding. I think srw and do them for erosion controll. 4' doesent hardly have to be enginered give me a break. It does require geo-grid though. I think your uncle justs wants your business. I use allen block and im not going to start a pissing contest of what is the greatest block. My factory rep who has seen around 20 of my 180 plus walls has seen my process how i install. she like my work and says i over kill with grid and gravel which made me feel good. Also stated with my experience that i dont need to contact them, but they could get me an engineer if needed for larger walls. I was bidding one last year for a homeowner 25' in height my rep met with me and homeowner and said this would require one.
Mike

GreenMonster
08-22-2006, 11:42 PM
b4 you do much more digging around there, you might want to call 1 888 dig safe.

Compaction (plate/jj), geo-grid, drainage, 3/4" cbr, angular drainage stone, are all NECESSARY ingredients to build the wall that you're describing. An engineer..... I believe that might be a little overkill for what you're talking about, but certainly a 4'+ wall with a slope behind it and questionable soils has some special considerations.

If you really want to do this yourself, I would definately recommend learning the proper methods for installation, otherwise you'll have wasted a lot of time and money on a wall that will likely settle or even fail in the future. If you decide you might want to hire a capable contractor, give me a call, I work in your neck of the woods. I'm in the YP.

crab
08-22-2006, 11:55 PM
what you need is shrubs to cover up those ute boxes. i really don't see why continuing the grass slope wont work.civil engineer much to vulgar display of power.

XXL Hardscaper
08-23-2006, 01:14 PM
I think he was just stacking them to see what they look like, i have done that for customers at times when im bidding. I think srw and do them for erosion controll. 4' doesent hardly have to be enginered give me a break. It does require geo-grid though. I think your uncle justs wants your business. I use allen block and im not going to start a pissing contest of what is the greatest block. My factory rep who has seen around 20 of my 180 plus walls has seen my process how i install. she like my work and says i over kill with grid and gravel which made me feel good. Also stated with my experience that i dont need to contact them, but they could get me an engineer if needed for larger walls. I was bidding one last year for a homeowner 25' in height my rep met with me and homeowner and said this would require one.
Mike

Mike I am not doubting your expertise in walls. I know that in the counties in which I work that there are height restrictions for non engineered walls. 1 county is as short as 30", so in that county you need stamped drawings to obtain a permit to build a wall that is less than 3 ft. It all depends on were you work and whether or not you do things by the book. There is a contractor around here who will build 5 and 6' tall walls with no engineer, no grid, In proper drainage, and allot of glue. Thats not me, do it right or don't do it.

kaig
08-23-2006, 02:46 PM
for the input. I guess I'll have to use grid, though I'll wait to see what my real height turns out to be, which I guess I'll only be able to tell once most of the digging is done.

Some more comments:


Yeah, those electrical/cable/phone boxes are ugly. On the bright side, looking from the usual angle they appear to uglify my neighbors' lot, not mine. But putting some shrubs there sounds like a good idea anyway.
I was contemplating 800-DIGSAFE, but then didn't get to doing it. All the utilities are in PVC conduit, and I know where they're running (well, I know what the plan says where they should be running). Since I'm hand-digging, I think the risk is real minimal. But I might call anyway, cheap insurance.
GreenMonster, and Mike33, I've seen your work (online) and think you're doing a great job. In fact, Greenmonster33 not only builds awesome walls around here, but also documented some of his jobs real nice in some threads here. That's where my inspiration for building a wall myself comes from :).


My dad's a retired civil engineer in Germany. Maybe I'll get him to read through the engineering materials, though I doubt he ever did a retaining wall in his life.

Anyway, one remaining question (for GreenMonster, I guess), would you give me a quick heads-up on the permit / engineering requirements in NH?

Mike33
08-23-2006, 06:37 PM
Mike I am not doubting your expertise in walls. I know that in the counties in which I work that there are height restrictions for non engineered walls. 1 county is as short as 30", so in that county you need stamped drawings to obtain a permit to build a wall that is less than 3 ft. It all depends on were you work and whether or not you do things by the book. There is a contractor around here who will build 5 and 6' tall walls with no engineer, no grid, In proper drainage, and allot of glue. Thats not me, do it right or don't do it.
I was more less touching on his spec that maybe it might be 4' in height, which it didnt seem to be a problem. What counties are you referring to in W.Va. that recquires that? I would like to know that for my own personel knowledge. I do work in Mineral county and it appears that people can build any thing walls, house, barn, etc., with out any zoning isssues. In fact every one is moving there for this reason. Yes i see guys building walls who dont care also,, no grid, footers, adequate stone, or proper drainage.
Mike

XXL Hardscaper
08-24-2006, 12:44 PM
I was more less touching on his spec that maybe it might be 4' in height, which it didnt seem to be a problem. What counties are you referring to in W.Va. that recquires that? I would like to know that for my own personel knowledge. I do work in Mineral county and it appears that people can build any thing walls, house, barn, etc., with out any zoning isssues. In fact every one is moving there for this reason. Yes i see guys building walls who dont care also,, no grid, footers, adequate stone, or proper drainage.
Mike

80% OF my work is in Maryland and No. VA., I dont know what the restrections are for the counties in W. VA. havent done any walls there.

DVS Hardscaper
08-26-2006, 01:27 PM
XXL -

There is not one answer for this gentleman.

One can start with calling a competent contractor. A competent contractor will then visit the site and will then contact an engineer. Known as 'Turn Key'.


Great to hear about your uncle. I have a brother in law that is a geo-technical engineer in the Manassas / Fairfax / Leesburg area. Maybe they know each other?

fall46
08-28-2006, 12:35 AM
Kaig,

Start with reading this link http://www.idealconcreteblock.com/contractors_corner.cfm.

Click on the section on the top left .....print the pages read them over and then re-read them. (Especially the first couple pages) Any questions use the search function on this site to get clarity on topics your confused about. I'm a homeowner as well ........but have built some retaining walls and paver patios...and their not as easy as u think. Using a wheelbarrow and a hand tamper will not suffice by looking @ your project...Unless you are training for a triathlon and have 2 + weeks to work on the project 8+ hr days...U will @ the very least need to rent a bobcat if u decide to do this yourself and a hand tamper is out of the question as well. This is not to say u cant pull this off as homeowner... but that’s a fairly big project by looking @ the pic. Lot of variables that make it somewhat complicated... including native soil or fill from house foundation, fairly decent slope, potential for engineer recommendations as wall height may exceed 4+. As for building this wall for "erosion control" u may have used that characterization loosely and intended to accommodate a change in "grade". Although contrary to what XXL hardscaper said SRW's can and do serve as a form of erosion control.. In fact if you look on page 1 (third paragraph) from the block manufacture they explicitly say SRW's "provide erosion control"..... However, these walls are almost always first spec'd by an engineer.

If your inclined to do this yourself and have the time and are willing to bust your arse. I would recommend seeing if any contractor will work on a consultation basis, or consulting basis in your area: they could provide a layout, expertise in soil conditions, potential use of geo-grid and whether the need for a engineer is necessary. Correct base material and free draining stone to use etc...... Which in the end may be better off paying them to do it all. Read the articles and research questions u have on the site then report back what direction you’re leaning towards

kaig
08-28-2006, 12:32 PM
Thanks for the link to the reading material -- I've been reading the Allan Block tech sheets, but this one looks even more comprehensive, so I'll dig into it.

Here are some pics of the current state of the excavation -- no base trench yet, as I'm not quite decided as to the exact position / shape, but the rough outline is there. I'll most likely go 5 blocks (40" minus ~5" buried, so roughly 3') high at the highest point, which should take care of all stability concerns, and helps with the cost, too. The mattock/shovel/wheelbarrow method is a bit of a pain, but then, the visible progress at the end of the day kind of makes up for it. Most of the dirt, under a thin layer of topsoil which I stripped off, is pretty sandy fill, and yesterday's rains confirmed, that it drains quite well...

Oh, and I cannot help a general comment to *some* of the contractors here. I guess you have a point that being a homeowner, I shouldn't post here, and so someone feel free to move it the homeowner's help forum. However, I really don't think some of the attitude I got here is appropriate. Not having the title of contractor doesn't necessarily mean one is not capable of doing a good job. Sure, some people are just going to buy block, stack it onto the bare ground with no base / drainage / etc and wonder why things fall apart the next year. I've actually been doing my research, which is why I've been reading professionals' posts here, to learn how to do things properly. Just making unfounded claims may be intended to point out who's the professional, but really achieves the opposite.

No contractor is losing a project here because the homeowner thinks he can do it himself. If I weren't doing it myself, I'd put on grass seed and straw blankets, and there would be no retaining wall project. I don't think it'd hurt to offer more advice than, if you want to have it done professionally, contact me. Sure, I'm asking professional advice for free, and in a direct business sense, that's bad. OTOH, I've been giving free advice and doing free work on the internet on a very different project (Linux, a free operating system) where I can use my professional knowledge. I have no money to show for doing so, but it was still an enjoyable experience.

But even in the business sense, helping a customer on a DIY project may build a relationship, and when that customer tackles a new project which is too big for him, he'll likely remember someone who helped him out. Or when he's asked for referrals. (On that note, I'm on the landscaping/maintainance committee for our HOA here, 40 lots. I don't know if there'll ever be hardscaping projects coming out of it, I just want to make the point that it doesn't hurt to treat people nicely and with respect even if you can't see any immediate money coming out of it).

XXL Hardscaper
08-28-2006, 04:24 PM
XXL -

There is not one answer for this gentleman.

One can start with calling a competent contractor. A competent contractor will then visit the site and will then contact an engineer. Known as 'Turn Key'.


Great to hear about your uncle. I have a brother in law that is a geo-technical engineer in the Manassas / Fairfax / Leesburg area. Maybe they know each other?

Agreed !

Yes maybe your Bro in law knows him his office is in Alexandria, He is not only a Civil Engineer he is also a Hydro Geological Engineer.

jazak
08-28-2006, 04:51 PM
Thanks for the link to the reading material -- I've been reading the Allan Block tech sheets, but this one looks even more comprehensive, so I'll dig into it.

Here are some pics of the current state of the excavation -- no base trench yet, as I'm not quite decided as to the exact position / shape, but the rough outline is there. I'll most likely go 5 blocks (40" minus ~5" buried, so roughly 3') high at the highest point, which should take care of all stability concerns, and helps with the cost, too. The mattock/shovel/wheelbarrow method is a bit of a pain, but then, the visible progress at the end of the day kind of makes up for it. Most of the dirt, under a thin layer of topsoil which I stripped off, is pretty sandy fill, and yesterday's rains confirmed, that it drains quite well...

Oh, and I cannot help a general comment to *some* of the contractors here. I guess you have a point that being a homeowner, I shouldn't post here, and so someone feel free to move it the homeowner's help forum. However, I really don't think some of the attitude I got here is appropriate. Not having the title of contractor doesn't necessarily mean one is not capable of doing a good job. Sure, some people are just going to buy block, stack it onto the bare ground with no base / drainage / etc and wonder why things fall apart the next year. I've actually been doing my research, which is why I've been reading professionals' posts here, to learn how to do things properly. Just making unfounded claims may be intended to point out who's the professional, but really achieves the opposite.

No contractor is losing a project here because the homeowner thinks he can do it himself. If I weren't doing it myself, I'd put on grass seed and straw blankets, and there would be no retaining wall project. I don't think it'd hurt to offer more advice than, if you want to have it done professionally, contact me. Sure, I'm asking professional advice for free, and in a direct business sense, that's bad. OTOH, I've been giving free advice and doing free work on the internet on a very different project (Linux, a free operating system) where I can use my professional knowledge. I have no money to show for doing so, but it was still an enjoyable experience.

But even in the business sense, helping a customer on a DIY project may build a relationship, and when that customer tackles a new project which is too big for him, he'll likely remember someone who helped him out. Or when he's asked for referrals. (On that note, I'm on the landscaping/maintainance committee for our HOA here, 40 lots. I don't know if there'll ever be hardscaping projects coming out of it, I just want to make the point that it doesn't hurt to treat people nicely and with respect even if you can't see any immediate money coming out of it).


You did all that by hand?!?:confused: :dizzy:

ferdinand711
08-28-2006, 04:55 PM
I'm admittedly just a homeowner, but I thought I'll see if the pros have some advice for me, and there's a potential for someone to make a little bit of money in this, too.

I bought a new home (Seacoast, NH) last year which is on a pretty sloped lot. We had some heavy rains after the (late) hydroseeding last fall, and I didn't really get much of a lawn, which made me a hobby landscaper this year -- I admire you guys doing this every day, as it's serious work, but I find it quite enjoyable, too.

Anyway, I found lawnsite in my quest to learn about lawns, stumbled upon the hardscaping forum and found a lot of real nice work here. So I decided I want to put in small retaining wall, for one because I like the looks and would like to learn how to do it (always up for something new). To justify the expense and effort, I'm telling myself it should also be helpful in dealing with the erosion problems on the slopes. Now, I'm not much of a promising customer, as, like I said, I'm in it for the experience of doing it myself, and neither could I afford spending a couple of thousand of dollars. In the pic below, the steepest slope is in the front left, about where I put in a couple of blocks just to get a feeling for how it would look (no base, no drainage etc at this time, but I will be doing it right).

In order to save expenses, I started to scrape of the existing top soil (will reuse later), and I want to just redistribute the fill (sand with bricks is what I've found so far), not bring in or haul out more stuff. However, I will obviously need the blocks, gravel, base material. If any of the NH guys here are interested in just selling me the materials (+ delivery), I might be up for that (I suppose you get stuff at a discount, so you may make a bit of money without any actual work).

And then I have a couple of questions, too, any kind of input would be appreciated.

For one, the wall is next to a patch of wooded land which was saved during the construction. However, the builder piled up fill right next to some of the trees to build up the slope, so I suspect they may be doomed anyway. I suppose by removing some of that close fill and then putting in the wall at some distance, I'm at least not going to make the situation worse?

2nd issue, on top of the hill in front of the house is the septic leach field. I'll be pretty far away from it (the wall will go only about 30' back, which is roughly where the field starts, but I'll be at the foot of the slope while the field is obviously in the flat part on top). Just want to make sure I'm not potentially overlooking any issues there?

The wall will be maybe 4' high at the highest point (front left), lower in the back, as the terrain (wooded patch) slopes up, so I don't think I have any engineering / grid issues. Does anyone know NH rules on engineering, permits, etc?

How do you guys go about designing/estimating height & materials? If it were a straight wall at given height/length, that'd be quite easy, but as I said, I want to keep the net amount of soil/fill the same, and it seems not easy for me to guess at what distance from the wooded patch the wall should be, how high, how to taper it off at the ends or turn it in, etc.? Any tips on that, or is that just what comes with your experience? I'm currently thinking I'll just form the new shape with shovel, wheelbarrow etc until it looks right to me, and then see how tall / long the wall is going to be and order materials accordingly.

I'm planning to do basically everything with handtools, which actually seems quite doable, even though it'll take quite a bit of time (but saves on the gym ;) The one thing I'm wondering about is a plate compactor, how necessary is that over handtamping? The problem is, this is going to be a weekend project which will take a while to finish, and renting a compactor a couple of times sounds quite expensive, besides I'm not really quite sure how to haul it -- I assume these things are too heavy to be moved by a single person?

Finally, though I should have asked that first, is a wall going to look good there? And is it going to help with the erosion?


sir, my advise is for you to call a PRO and let them handle everything because what you got is not a homeowners weekend project.

have a good day!

jazak
08-28-2006, 06:49 PM
sir, my advise is for you to call a PRO and let them handle everything because what you got is not a homeowners weekend project.

have a good day!

Ditto the above!!:clapping: :clapping: :clapping:

GreenMonster
08-28-2006, 08:47 PM
Oh, and I cannot help a general comment to *some* of the contractors here.
I don't think it'd hurt to offer more advice than, if you want to have it done professionally, contact me.

Kaig, I hope your comments aren't directed at me, because I really have no issues at all with you doing it yourself. You have to realize though, you're asking for advice on what is the highest risk landscape component -- retaining walls. There are several important factors to building an SRW, including proper base preparation, base and consolidation zone compaction, proper placement and installation of geo-grid, not to mention grid length and strength, drainage location, etc etc etc. Many of us have gone through professional training to collect the knowledge we have. For the wall that you are going to build, which is beyond "basic", the techniques you need to employ are not that easily related through a landscape forum. The other thing you have working against you is that many of us are backed up not only with work, but quotes and other jobs to look at. This is a time of the year where time is definately at a premium. Hang around here long enough and you'll see a lot more activity from many of us in the winter months than you will now.

So, if you want to hear that it's possible to do this wall yourself, sure it is. But using strictly hand tools, you're pushing your luck. If you're going to invest the time and money on the wall stone and it's installation, at an absolute minimum you should be using a plate compactor for base and backfill. I also see that you're using Allan Block. You should be passing a plate compactor directly over the blocks of each course after the base course.

I wish you had mentioned Allan Block before. Whereas you're backfilling by hand, I definately would have recommended a solid block that didn't require filling of the cores. Just one more PITA step with a skid steer, nevermind by hand.

So, anyway, are you doing any grid pulls with this wall. I know it's only 3', but I would have a grid pull after the 1st and 3rd courses due to the slope behind the wall. Hopefully, your base excavation has gotten you below any "fill" that was pushed into this area from the construction process. If you're not pulling out newly excavated/placed material, your base still has the ability to settle over the years due to unstable soil below.

I don't know what the permit requiements are in Lee. It's by the town in NH. Call the town hall and see if you need a building permit. If the wall is <3', probably not.

Finally, let us know how you like Allan Block. I started off using AB, and after using some others, I can't stand it now. I'm finishing an AB job right now, and I'm really considering NOT offering AB walls anymore, even though I'm certified with them. Their corners are the worst of all. Hopefully you don't have any corners in your wall.

Again, keep in mind that you wall is somewhat significant, and some of the best advice really would be to call someone with experience. Knowing that you don't want to do that, read up as much as you can on the AB tech sheets (which are pretty decent) and rent the tools that are REQUIRED in order to build that wall properly. Good Luck.

Mike33
08-28-2006, 11:59 PM
Kaig, I hope your comments aren't directed at me, because I really have no issues at all with you doing it yourself. You have to realize though, you're asking for advice on what is the highest risk landscape component -- retaining walls. There are several important factors to building an SRW, including proper base preparation, base and consolidation zone compaction, proper placement and installation of geo-grid, not to mention grid length and strength, drainage location, etc etc etc. Many of us have gone through professional training to collect the knowledge we have. For the wall that you are going to build, which is beyond "basic", the techniques you need to employ are not that easily related through a landscape forum. The other thing you have working against you is that many of us are backed up not only with work, but quotes and other jobs to look at. This is a time of the year where time is definately at a premium. Hang around here long enough and you'll see a lot more activity from many of us in the winter months than you will now.

So, if you want to hear that it's possible to do this wall yourself, sure it is. But using strictly hand tools, you're pushing your luck. If you're going to invest the time and money on the wall stone and it's installation, at an absolute minimum you should be using a plate compactor for base and backfill. I also see that you're using Allan Block. You should be passing a plate compactor directly over the blocks of each course after the base course.

I wish you had mentioned Allan Block before. Whereas you're backfilling by hand, I definately would have recommended a solid block that didn't require filling of the cores. Just one more PITA step with a skid steer, nevermind by hand.

So, anyway, are you doing any grid pulls with this wall. I know it's only 3', but I would have a grid pull after the 1st and 3rd courses due to the slope behind the wall. Hopefully, your base excavation has gotten you below any "fill" that was pushed into this area from the construction process. If you're not pulling out newly excavated/placed material, your base still has the ability to settle over the years due to unstable soil below.

I don't know what the permit requiements are in Lee. It's by the town in NH. Call the town hall and see if you need a building permit. If the wall is <3', probably not.

Finally, let us know how you like Allan Block. I started off using AB, and after using some others, I can't stand it now. I'm finishing an AB job right now, and I'm really considering NOT offering AB walls anymore, even though I'm certified with them. Their corners are the worst of all. Hopefully you don't have any corners in your wall.

Again, keep in mind that you wall is somewhat significant, and some of the best advice really would be to call someone with experience. Knowing that you don't want to do that, read up as much as you can on the AB tech sheets (which are pretty decent) and rent the tools that are REQUIRED in order to build that wall properly. Good Luck.
Very good post, all your points i have to agree with except i use ab all the time. However i dont argue brand of block here its like the ford and chevy issue. The corners do suck. I dont run the damper directly over the block i guess just for gp. Any way that was great advise in detail and if followed he should be successful. I dont care either who build there own wall but with out the right equipt. and tools it is very tough. The last pic and it might of been my eyes it didnt look like enough excavated for proper backfill of gravel. The front wall is taking all of the load dont be afraid to overkill it with stone for drainage,
Mike

GreenMonster
08-29-2006, 11:48 PM
Very good post, all your points i have to agree with except i use ab all the time. However i dont argue brand of block here its like the ford and chevy issue. The corners do suck. I dont run the damper directly over the block i guess just for gp. Any way that was great advise in detail and if followed he should be successful. I dont care either who build there own wall but with out the right equipt. and tools it is very tough. The last pic and it might of been my eyes it didnt look like enough excavated for proper backfill of gravel. The front wall is taking all of the load dont be afraid to overkill it with stone for drainage,
Mike

Yes, on that last pic, seems like the backfill is not proper. Also, the pic doesn't really tell us, but you can't build AB more than one course at a time, cuz you need to fill the cores.

Mike, run the plate over the blocks, and you'd be amazed how much more stone ends up in the cores.

I've used a lot of AB too, Mike. It's what I started with, and there is a lot of it used around here, so I assumed it was best. Not only do I know find it exteremely labor intensive and difficult to work with, but I find the quality to be very poor (which may be mostly in part to the local mfg). Just for sh1ts and grins, you outta try a couple others and see the difference.

Versa-Lok is quite a distance from me, but I'm giving them a call later this week. I'm finishing an AB job tomorrow, and it may very well be the last AB wall I ever build.... seriously.

kaig
08-30-2006, 10:34 AM
Well, I hit my first problem yesterday, a tree stump/root ball buried where I was digging the trench for the foundation. It's not even that large (as far as I can tell so far), but two hours of digging later it's still not moving a bit... But I guess it wouldn't be fun if there weren't those little surprises.

Thanks for your replies, guys, lots of useful info. I hope I didn't come across too harsh last time, I didn't mean to.

Another, (repeated) comment, yes, there's no proper backfill in the pic, but the blocks aren't even in their final place yet (in fact they've already moved into another, temporary, location).

So GreenMonster, where's the pics for your latest wall? :)

GreenMonster
08-30-2006, 09:02 PM
Well, I hit my first problem yesterday, a tree stump/root ball buried where I was digging the trench for the foundation. It's not even that large (as far as I can tell so far), but two hours of digging later it's still not moving a bit... But I guess it wouldn't be fun if there weren't those little surprises.

Thanks for your replies, guys, lots of useful info. I hope I didn't come across too harsh last time, I didn't mean to.

Another, (repeated) comment, yes, there's no proper backfill in the pic, but the blocks aren't even in their final place yet (in fact they've already moved into another, temporary, location).

So GreenMonster, where's the pics for your latest wall? :)

ah, stumps. Lots of fun there. Be sure once you have that out, you bring up the new fill (cbr or stone) in lifts so that you get good compaction. A jumping jack would be good for that.

As far as pictures go, I had a thread I was trying to keep up with, but I haven't added anything in a few months. Just been too busy. We'll finish our AB job tomorrow, this pic is a Techo wall (my new favorite) we did before the wall we're on now. It's 5" Creta in rusty grey. Sorry, the only pic I have, the wall isn't complete.

This wall had a nice surprise... about 3' of loam where it was going. So, now the wall is sitting on a 3' crushed stone base.

Mike33
08-30-2006, 09:57 PM
Yes, on that last pic, seems like the backfill is not proper. Also, the pic doesn't really tell us, but you can't build AB more than one course at a time, cuz you need to fill the cores.

Mike, run the plate over the blocks, and you'd be amazed how much more stone ends up in the cores.

I've used a lot of AB too, Mike. It's what I started with, and there is a lot of it used around here, so I assumed it was best. Not only do I know find it exteremely labor intensive and difficult to work with, but I find the quality to be very poor (which may be mostly in part to the local mfg). Just for sh1ts and grins, you outta try a couple others and see the difference.

Versa-Lok is quite a distance from me, but I'm giving them a call later this week. I'm finishing an AB job tomorrow, and it may very well be the last AB wall I ever build.... seriously.
Okey mark ill try running the tamper over the block. Again opinions are like ass holes but my theory has always went with the open core for the reason of more gravel helping drain if that makes sence. I looked at versa lok few weeks ago i was building 3 walls in Garrett county Md. and there is a ab dealer right there. They also sell versa lok and the damn thing seemed so heavy to handle. In fact they were supposed to even have what they call a versa holder or something like that to sit the block. I have never been a fan of the pin system either i prefer the lip on the block for my set back. versa lok was priced a little cheaper than ab but there coverage wasent as good . It would probably all come in the wash as same price though. Your pic there on that wall , i am impressed with the face texture. Keep up the good work.
Mike

GreenMonster
08-30-2006, 11:44 PM
Okey mark ill try running the tamper over the block. Again opinions are like ass holes but my theory has always went with the open core for the reason of more gravel helping drain if that makes sence. I looked at versa lok few weeks ago i was building 3 walls in Garrett county Md. and there is a ab dealer right there. They also sell versa lok and the damn thing seemed so heavy to handle. In fact they were supposed to even have what they call a versa holder or something like that to sit the block. I have never been a fan of the pin system either i prefer the lip on the block for my set back. versa lok was priced a little cheaper than ab but there coverage wasent as good . It would probably all come in the wash as same price though. Your pic there on that wall , i am impressed with the face texture. Keep up the good work.
Mike

btw, we run the small plate over the blocks, 3000#.

I agree that the extra stone probably helps with drainage, but I'm just getting to the point where all the extra labor is not worth it. Plus, whereas the stone is being filled in the middle of the block, it always seems like stone is in the way for you next course no matter how well you clean it off. Plus the friggin corners -- I'm ready to kill someone!!! And the front lip setback is a major PITA when doing 90 degree stairs. You have to notch out the bottom of EVERY block in order to get a straight face on your steps. UGH!!!!

Your walls look good, Mike, and maybe you're getting better AB quality with your mfg, but I just think you should keep an open mind and maybe try another product, maybe on small project. I've tried others and I like almost all of them better than the AB.

Mike33
08-31-2006, 10:46 PM
btw, we run the small plate over the blocks, 3000#.

I agree that the extra stone probably helps with drainage, but I'm just getting to the point where all the extra labor is not worth it. Plus, whereas the stone is being filled in the middle of the block, it always seems like stone is in the way for you next course no matter how well you clean it off. Plus the friggin corners -- I'm ready to kill someone!!! And the front lip setback is a major PITA when doing 90 degree stairs. You have to notch out the bottom of EVERY block in order to get a straight face on your steps. UGH!!!!

Your walls look good, Mike, and maybe you're getting better AB quality with your mfg, but I just think you should keep an open mind and maybe try another product, maybe on small project. I've tried others and I like almost all of them better than the AB.
I dont know about any better quality, we have a lot of waste at times with chips in the corner of the block. We noticed this in the earth blend. Last week we laid 10 skids or red and had maybe 3 bad block. Today we built a wall 5 skids in lime stone blend 2-3 bad. We had back to back jobs in july earth blend each job 16 to 20 skids and had 5 bad block per skid. Yes there corners suck, i ve been doing these since about 98 and thay improved a little. I told my sales rep they needed to hire a uneducated idiot for a engineer or we would design a corner block that would work. That was like a fart in church. We have built very few steps i try and avoid them and try talk customer in to pouring them but we end up doing a few. Out of my around 180 walls i probably have a total of 10 steps. What we did this year we sat ab lites in the cap tread with the lip of the lite on the back of the cap. This seemed to tie things togeather better and made the step around 6". But i feel they are still a sloppy job for steps with the lip for the set back on the sides the stair case gets wider then you have to cut a block for the steps. the little pieces to me makes the job look bad.
Mike

kaig
10-20-2006, 10:54 AM
Alright, time to revive the thread because the wall is done (well, almost, still need to do caps in the far corner and glue all caps).

I'm very happy with how it turned out. Now of course I have my fingers crossed that I built it well enough that it'll last.

GreenMonster
10-20-2006, 11:02 AM
Looks good. I like the turn in at the top. The only thing that I immediately see is the caps on the end, we would have put a split face on the ends. I'm also curious how you cut your caps on the curves, and how they turned out for you.

It's looks like you have enough block buried for that size wall. As long as you have a good drain field, I'm sure the wall will be fine.

kaig
10-20-2006, 11:12 AM
Well, of course I learned a lot in the process, too. Maybe it's useful for someone else, too (not the pros, but maybe some beginners):


It was a lot more work than I thought. Of course, I did it all by hand, which probably no sane person would do. Not only the excavation/fill with drainage stone/backfill/tamping, but also particularly getting the base course straight and level, and the caps. The actual wall building went relatively fast, but preparation as well as the final touches took their time.
I also badly exceeded my budget. That was mostly caused by changes as I went along (one additional course on top, the additional turn-in at the front corner), but also due to bad judgement from the start (I only guessed the overall length and wildly underestimated it, didn't really factor in the caps, ...)
It's possible to do it by hand. It's real strenuous sometimes, but overall it was a lot of fun, and you know what you've done at the end of the day. I guess the whole project took me like two months or so, but that's because I only worked when I had the time, weekends and nights.
I now understand why everyone's bitching about the Allan Block corners. And I understand why the instructions tell you to step down using a corner block turned into the backfill (because otherwise there's too little support for the cap).
I did all the cutting (mostly caps) with a cheap circular saw and a cheap ($15) diamond blade. I was amazed at how well that worked, cuts concrete like butter. The only drawback is that it doesn't have enough depth, so I had to cut twice, once from the top and once from the bottom.

One final question, as I plan on gluing down the caps eventually, I bought some polyurethane glue. This one comes in a big cartridge and is a general construction adhesive. There also was a glue which specifically stated that it remains flexible, for glueing caps to reatining walls, but it only comes in a small size and is quite a bit more expensive. It was based on polyurethane, too, so I'm thinking I might just as well use the former?

kaig
10-20-2006, 11:31 AM
Looks good. I like the turn in at the top. The only thing that I immediately see is the caps on the end, we would have put a split face on the ends. I'm also curious how you cut your caps on the curves, and how they turned out for you.


Actually, the caps do have split faces, though I guess that's hard to tell from the pics -- I learned this from reading through the archives here :) . I cut the caps only on one side for the curves, so it's kinda asymmetric, but I like it. I don't have closer-up pics right now, I'll get some later.

Generally, getting the curves to look good was kind of a *****, too, even though the radius I went with is about 2 times the minimal radius. The set back would get too large and too much of the underlying lip was exposed, same thing with the caps. So I chiseled out pieces in the center of the bottom of the blocks / caps to make the groove which goes against the lip of the block underneath deeper.

GreenMonster
10-20-2006, 03:08 PM
Generally, getting the curves to look good was kind of a *****, too, even though the radius I went with is about 2 times the minimal radius. The set back would get too large and too much of the underlying lip was exposed, same thing with the caps. So I chiseled out pieces in the center of the bottom of the blocks / caps to make the groove which goes against the lip of the block underneath deeper.

Yep, you have to cut out a little of the lip on the 12 degree block so the curves look a little smoother. We stand the block on it's flat back, and take the cut-off saw to the lip, just to notch out a little. If you use the 3 degree, it isn't quite as noticeable, and you don't have to notch out nearly as many block. it also helps to get some juniors, which are 1/2 stretchers, and use those in the corners.

Anyway, it came out nice. Good job.

BTW, we only cut on side of the cap too. If you used something like Techo, Bolduc, or others, they offer tapered caps, and the asymmetry isn't as obvious.