You need to consult a licenced structural engineer in your area to get that looked at. A retaining wall that close to your house could very well be supporting the homes foundation, not to mention the fact that it is supporting a huge load just from soil. For perspective, I designed a retaining wall for a home once that was 6' tall. We had to put in retaining blocks that were each 1 cubic yard of poured concrete and weighed around 10,000lbs, they had to be no more that 3' apart, were 6' from the wall, and each tied into the concrete retaining wall with 3 1" thick stainless steel rods.

 

Oh my gosh I'm terrified just looking at the pictures. I'm sorry you're dealing with this. So close to the house!

 

What is your budget?

I'm guessing it needs to be in the $X0,000 range.

If it were my home, I'd come about 10 feet further from the house, build a brand new retaining wall probably with stone of some kind, and backfill everything and remove the old wall carefully as you go.

Disclaimer - I'm not a structural engineer and you should absolutely hire one as suggested - there is a way to do this I'm sure that will leave you with a more usable and valuable yard.

As a contractor for landscaping, I'm not passing on a job like that unless someone tells me their budget is super small. Otherwise I would hire an engineer and a company that does retaining walls and act as the GC for the project.

 

Those "retaining walls" are really built all wrong. It is more of a dirt fence than a retaining wall. Clearly built by amateurs. There are no dead men, or tie backs, anywhere on the wall that I can see - nothing to anchor the wall against blowout or bowing.

Also cannot tell from photos but I bet the wood makes contact with the ground the entire length of the dirt fence, leaving no way for moisture to drain away from the back of the cross ties, which is why they all rotted out.

I have built cross tie terraces that made terrace levels on sloping lakeside lots, but the walls were properly dug into the hillside and cross ties stood on end resting on granite gravel for drainage and concreted into place in augered holes, with gravel behind each horizontal cross tie and each terrace back filled in lifts as each tie was placed. The water has to have a way out from behind the wall to relieve hydrostatic pressure or the wall will bow out or blow out, or rot out and fail.

The biggest problem is that building perched on the top of the upper level. Without seeing the foundation itself there is no way to tell if the "wall" or dirt fence can be moved without undermining the foundation or causing a collapse of the foundation in that area.

If it was me, I would only use stone and concrete for a wall with a building on top. The terraces I built were for foot trails and dog paths in the woods on lakeside lots - no buildings on top. Too much weight for wood to hold up over time.

It really depends on your budget and time horizon.

Here is a link to what a correctly built railroad cross tie retaining wall should look like: https://m.youtube.com/watch?v=WeKkGiHshLs

You need competent professionals to look at your situation.

I worked with civil engineers on my wall designs before building them.

They are still structurally sound thirty years later - I saw pictures of them recently. The wood has to be able to dry or it will rot out.... Good luck on your project!

 

Sell the house

 

Don't get too afraid of this job. The existing retaing wall looks far enough away from the homes foundation that as long as the house has proper footings you should be ok to tear down the old wall and build a new one. I would suggest a concrete landscape block wall built by a proper contractor or at the very least designed by a goetechnical engineer and constructed properly. Check with your local building department as you may need a permit for a wall over a certain height. It will of course be expensive but not impossible.

 

Do you have a basement? If so your foundation is likely deep enough that the retaining wall is not supporting the house, as @Shindoman said. If you have the original plans for the house that would help. My guess is this terraced retaining wall system was built as a way to deal with the grade change from upper to lower level and also provide a large and flat-ish usable back lawn, as opposed to a lawn that is one long slope. If you want some sort of ramp, you may find some inspiration in the Bank Barns of Pennsylvania and New England.

An engineer will likely recommend a keystone wall, as they are often the most affordable to construct assuming they are only retaining the weight of the soil, not the house.