13

"Landscape Timber" or, sometimes, "used railroad tie" - but "landscape timber" is what you'll find at most typical lumber suppliers. They will typically last several years - if well pressure-treated, longer. It's hard to know if they are really well pressure-treated until they start failing and you look at a calendar to figure out how long it's been. ...


10

It's quite hard to tell how big this wall is but you stated it's 3-4' tall. It looks like it was built simply as a vertical wall. There's nothing you can do about it. It was inevitably going to tip over. So yes, you do have to dig it out. If you want to replace it with timber, you need to add something called deadmen to it. A deadman is a timber that runs ...


6

I would cut off the timber in the ground using a Sawzall type tool (reciprocating saw) that has a long rough cut blade installed. You can get blades as long as 12 inches that can easily reach into tight spots and cut the wood. Soil will wear the teeth away fairly quickly and so be prepared to replace the blade. I've used this technique to cut roots free ...


6

I watched my fence installers and there where some areas that had a lot of stone. They would take a pointed metal rod and jam it into the hole to loosen up the rock and then use the post hole digger to get the loosened rock out. He alternated between the pointed rod and the post hole digger. Two men dug 9 holes by hand and finished the fence in one day.


6

First and foremost, will setting two posts in concrete behind this wall create any structural risk to the wall? You will not be adding any loads to the retaining wall that are of much concern. The wood screen wall is relatively very light so not adding surcharge to the soil behind the retaining wall and any forces from wind are relatively minor. The gravel ...


6

Counterintuitively, you usually want the holes in drainage pipe to point down, not up. This way, water from below can get forced up into the pipe from underneath, which then has a low-resistance path to flow away. If you install a pipe that only has holes on top, the pipe will want to float on top of whatever water is there, until the water level covers the ...


5

You can hold up 2' of dirt with wood structures. That's essentially what wood planter boxes are. But will it look good? Probably not...at least, not over time. Wood is flexible, gets wet, gets sun damaged, and the posts supporting it will suffer the same fate. If you don't care about looks, then it's probably OK, but if you want it to look OK over time, I'd ...


5

Once it's in place most gravel is not all that mobile, but it's also not hard to dig. I would not bother with a power auger, a clamshell posthole digger should get it done easily. I've just revisited some areas I backfilled with gravel to make some modifications, and got in just fine with a clamshell and a shovel - any large rocks were not in the area I ...


5

What you are showing is bare wood apparently without any treatment or coating. In that case the wood will shrink and swell due to humidity and, since this appears to be outside, rain, snow, etc. Wood changes dimensionally the most at right angles to the grain. In your case the grain is going horizontally and so the dimensional changes will happen most in ...


4

Building 23' of retaining walls is not a small task. This is a giant undertaking. So be forewarned. :) As stormy noted, 4' is typically the height you can go without having to trigger an engineering sign-off. However, some areas may also have a total height requirement as well. Personally, if I was buying a house with 6 levels of 4' retaining walls, I'd ...


4

They make them. Not concrete blocks per se but other precast concrete units. You'll need to find out if you're local suppliers carry them or you have a precast stone manufacturer near you. The family of products you're talking about, which includes not only the half round but other shapes, are called concrete coping stones. That should help you ask around ...


4

Can I convince you to not do this ? Honestly not trying to be an ass. Please, please - Get a quote from a company that builds retaining walls. The quote will cost very little or nothing. You will be shocked at the cost, and not in a good way. The quantity of material needed to build the wall, will amaze you. Please get a quote or two first. I promise ...


4

Classic example of a simple retaining wall built vertically - they ALWAYS fall over (except in the case of a LOT of permanent structure behind the face of the wall, making it more like one face of a box you can't see three sides of.) You'll have to dig. When you replace it, replace it with a wall that slopes, at least slightly, into the hill (ie, if it's ...


4

The answer is RAILROAD TIES. The timbers in your photo are Railroad Ties. The railroad will change the ties on a regular basis. They are impregnated with creosote and as a result they are very heavy. In Alaska the railroad will give the old ones away for free occasionally. I have built retaining walls with them. For the purpose of your fire pit area they ...


4

Does the fence need to be solid for privacy? If not, consider a chain-link fence. You set the poles, unroll the fencing along and attach it to the poles with wire clips, then if you want to avoid having it sag, you run a pipe or just a thick wire along the top through eyes on the tops of the poles. When you get to the end, you rent a come-along fence puller ...


4

This site prefers not to provide 'call a professional' answers and I might receive some less positive reception for this answer, but this is a case where I think that it is appropriate. My suggestion is to hire a local structural engineer to do a site visit and provide you with their opinion of the situation and additionally, if you prefer, a DIY fix ...


4

The normal way would be reinforcing bar around insides of the blocks, then add concrete. This is called a "bond beam". Blocks with open ends are used. If you use enough reinforcing it can be very strong. For your way stainless threaded rod, you probably need to go to a fastener specialist for that. (or stainless rod and you thread the ends, but ...


4

Bore a 4" hole and pour it full of concrete, so the rebar has 2" concrete cover.


4

In my experience it's nearly impossible to push such a concrete wall back to its original position. The best approach is to break it up and remove it and then if you want a wall there, replace it with one that has proper drainage so that it won't get pushed over again.


3

This is about load bearing and claims. The pressure associated with 2 ft of dirt is probably well within the load bearing specification of the blocks in question. 3 feet may not cause any issue, but you cannot hold the manufacturer liable if it collapses and/or if someone gets hurt. If you exceed the manufacturers specifications an inspector might have a ...


3

Coarser sand is better. Concrete sand would work much better than mason sand. When I used to do pavers we would use crusher dust. That being said, it's a patio and not a driveway or a road, so I don't think I would be overly concerned if I had already put down mason's sand.


3

I built a retaining wall in a situation very similar to what you described. In my case the wall drops approximately 12" over 40 feet. It has 3 courses of 6" Keystone wall blocks. The first course is mostly buried and the wall is about 12" high over most of it's length. I also put about 4" - 5" inches of drain rock behind it with a landscape fabric barrier. ...


3

Yes that is the way to do it without a cutoff blade, it is old school. But you must chisel in deep enough, completely around the block that is accessible, before you strike with hard blows to break it on the score line you made. I have done this with as little as an 1/8" deep score, although deeper is better for a more sure result. Go around the block in ...


3

I do not think you could rest a second unsupported wall on top of a retaining wall without long reinforcement members penetrating both the retaining wall and the wall on top. Otherwise the upper wall could topple. Perhaps the top wall should be a fence with posts embedded 18" in the earth on the sidewalk side of the retaining wall. Alternatively there could ...


3

Wow...there’s a lot of issues: 1) height, 2) non-reinforced wall, 3) load bearing, 4) moisture 1) This is a tall wall at 10’ or so. That means if it is a true retaining wall, it has a lot of stress on it if it’s load bearing, moisture bleeding through the wall, etc. 2) This is a “gravity retaining wall”. That is to say it’s a non-reinforced wall. Non-...


3

Although it looks to be functional at this point eventually the bottom tier will rot away causing the retaining wall to fail. You have a legitimate concern. There is no simple answer to this because the right answer is to rebuild the wall. I'm assuming here that the wall has compacted soil on the other side. Since the bottom tier is rotting, and if you're ...


3

I assume this is going to be a slab on grade house. I assume the plan is for rain drains which feed into a perimeter drain which goes out to the city storm drain. A 1m tall retaining wall is nothing. A nice flat backyard is good. Unless your lot is down slope from many other lots and there is a natural tendency for water to run into your yard and your ...


3

No need to purchase special braces, just use some common lumber. When i set fence posts I use a 2"x 4" and wood stake. Lay your 2x4 on your wall at angle, the farther the end that will be at the ground/stake is away from the wall the more lateral stability you will have. Secure the brace to the wall, you may need to add some scrap wood to attach ...


2

I would use a chain saw myself, but if you dig out adequate clearance, even a hand saw will work. You'd have to also dig clearance for a chain saw, running the chain in dirt is a bad thing. Thoroughly clean the chain after doing this work. You may find the wood is rotted beyond where you plan to cut. It's important to remove all rotted wood or else it will ...


2

There are too many unknowns to answer this question. What type of soil is there so a reasonable active pressure, passive pressure, and sliding resistance can be determined? What surcharge is on the 7" slab? How far from the face of slope is the wall located? What is the frost depth? What type of masonry? Grout? Mortar? Reinforcing? This wall is high enough ...


Only top voted, non community-wiki answers of a minimum length are eligible