Fixing uneven/bellied shed walls for home gym

caesar

Hey DIYers,

Bit of a long but I'm converting two old sheds into a home gym. The plan is to either knock the dividing low wall or if I can get away with enough space from one side, I'll close the divide off properly.

The thing is I've got a bit of a problem with the two side walls. They're uneven, and on top of that the shed doesn't look square. I was planning to use those walls for storage (weight plates etc.) as they're the longest wall. The end walls seem to be a fair bit better, confident they can be plastered.

Currently, the floor isn't level (by design) either. A fall was built-in towards the door for when they were being used for the farm. But I think I can easily sort that with a screed before putting rubber mats down.

With the walls, I was going to plaster them and do the floor after. But now Im concerned there might be too much that plastering won't fix.

To give you an idea of what Im talking about, the other adjoined sheds were an old house on the site sometime pre 1970. They have that chalky brittle lime plaster finish applied. As far as I know, all the walls were built using a timber casing with a concrete mix filled in. So no blockwork or cavity, but no cracks either. The sheds are dry and were recently re-wired.

And they were plastered on the outside sometime in the 80s/90s. There are no visible signs of cracks there either. For all, I know the walls might have steel in them. Still, they're uneven, a little bellied looking, which is most likely where the casing job wasn't great rather than a structural bulge. As an aside, I need to find something to remove the build-up of dirt!

But, the main thing is how would I fix the interior walls. I want them sorted before putting the equipment in. I've been toying with:

1. Build brick or block walls in front of them (about 2 metres high, up to the wall plate). The pluses are I get: a cavity (albeit a varying one!), a solid wall, a sound storage solution and a clean finish. The minuses are, I lose a fair bit of space, I'm rebuilding half the shed walls, and I don't think I could build directly on the floor. How would I know if I can?
2. Try plastering and see how it goes...
3. Line those two walls with a frame with 25mm plywood attached in such a way that I end up squaring the shed. I'd have to forget about storing anything on them. Im thinking I would need to build a frame and keep it out from the walls, to avoid reproducing the unevenness in the frame.
4. Build a casing and pour in the concrete to effectively refinishing the walls. Now is this a nonsense solution? Would the fresh concrete even bond to the existing walls? Im picturing the need to put a threaded bar (or somesuch) into the old walls at various points to tie it to the old wall. Still, vibrating might not be easy, so would I end up with loads of air pockets if I didn't?

Number 4 is definitely my most creative solution there. I figured I'd throw it out there for ye to pull apart :pac: But we have some old casing lying about from when we built a new slated shed. I'd use that.

GreeBo

I dont see why you need to square the walls just to store thing on them?

If its going to be something very heavy like weight plates then you are going to be anchoring it to the wall, but it doesnt have to be square, think along the lines of threaded bar so you can get the shelf as square as you want.
Alternatively and depending on the weight involved, have you thought about something floor mounted?

Either way, if its just a nice finish you want then either batten the walls or build an offset stud wall and plasterboard/OSB them.
You can still use the solid wall when fixing things, you just need longer fixings.

caesar

GreeBo wrote: »

I dont see why you need to square the walls just to store thing on them?

If its going to be something very heavy like weight plates then you are going to be anchoring it to the wall, but it doesnt have to be square, think along the lines of threaded bar so you can get the shelf as square as you want.
Alternatively and depending on the weight involved, have you thought about something floor mounted?

Either way, if its just a nice finish you want then either batten the walls or build an offset stud wall and plasterboard/OSB them.
You can still use the solid wall when fixing things, you just need longer fixings.

Yeah, you're right there re the squaring it up. I mentioned it as I'd be better sorting before doing anything major with concrete or plaster. But it's probably more a cosmetic thing. The only functional impact I can think of is when Im laying the rubber mats. I'd have gaps in parts if it weren't square. Arguably that's a cosmetic thing as well though.

I want a decent finish as much as anything—I need a training environment that I enjoy going into. Plus, I wouldn't put new equipment into it as is, but not building a new shed either.

I thought of battening the walls or using an offset stud (that's what I was getting at with number 3 there) and doing as you suggested anchoring to the wall behind. I figured I'd end up replicating the unevenness with battening to the existing walls, but as I think about it more, I could get around that easily enough. I'm favouring the stud with OSB or Ply, as if dampness from the outside wall became an issue, the battening would be snookered.

Floor storage won't be an option if I only use one side of the shed.

Different question

The equipment might be out of it by winter, but assuming it's not, would there be a risk of rust if I seal it better. Being a shed with a wooden door sitting off the ground, it's well ventilated year-round, but I thought of sealing it up with a new door. I'd then put a heater of some sort to heat the place quickly and safely for half an hour before training in winter, mainly because freezing barbells are not great on the hands or upper back. But I wonder if I'd be creating an environment that's more prone to holding moisture, albeit nicer for the hour Im in it.

Insulating is probably a waste of time as I don't plan (or see the need) to heat it at any other time day/year.

GreeBo

caesar wrote: »

Yeah, you're right there re the squaring it up. I mentioned it as I'd be better sorting before doing anything major with concrete or plaster. But it's probably more a cosmetic thing. The only functional impact I can think of is when Im laying the rubber mats. I'd have gaps in parts if it weren't square. Arguably that's a cosmetic thing as well though.

I want a decent finish as much as anything—I need a training environment that I enjoy going into. Plus, I wouldn't put new equipment into it as is, but not building a new shed either.

I thought of battening the walls or using an offset stud (that's what I was getting at with number 3 there) and doing as you suggested anchoring to the wall behind. I figured I'd end up replicating the unevenness with battening to the existing walls, but as I think about it more, I could get around that easily enough. I'm favouring the stud with OSB or Ply, as if dampness from the outside wall became an issue, the battening would be snookered.

Floor storage won't be an option if I only use one side of the shed.

Different question

The equipment might be out of it by winter, but assuming it's not, would there be a risk of rust if I seal it better. Being a shed with a wooden door sitting off the ground, it's well ventilated year-round, but I thought of sealing it up with a new door. I'd then put a heater of some sort to heat the place quickly and safely for half an hour before training in winter, mainly because freezing barbells are not great on the hands or upper back. But I wonder if I'd be creating an environment that's more prone to holding moisture, albeit nicer for the hour Im in it.

Insulating is probably a waste of time as I don't plan (or see the need) to heat it at any other time day/year.

If you are worried about moisture getting into the external wall then you are going to have a problem with anything that covers it, unless you have airflow to allow it to dry. Even with a air gapped stud wall, if the outer wall is wet to the point where its reaching the inside you are risking damp and mould.
At the very least you would want a vapour barrier on the inside to stop your own moisture from condensing on the cold external wall.

Exposed steel weights wil rust, I have barbells and plates in my garage and they have rust, the garage isnt wet or exposed, but its in no way sealed so the air will get damp if its a damp day and there is no heat source in there. It has a great airflow though