Hi this is my first post here. We are going to put a 10 x 8 room in our unfinished basement for our 13yr old. The problem is that the basement has some seepage and we are trying to spend the least amount of money as possible as this will be a temp room until we can add on to our whole house. A family member suggested using metal studs as a base for the flooring so the seepage wouldn't get into the wood of the walls or floors. Being a "temp room" some may say why worry about that, I'm allergic to mold and would prefer not to give a place for mold to start growing. My basic question is how many metal studs would we need to build the floor or how much weight would they each hold. I was looking at 1 10'stud every foot to 2 foot for the floor base. Any answers or other cheap suggestions are appreciated.

Thanks!
Yee

First, welcome to our site. I hope we can help you with this as well as any other questions you may have.

Some might disagree with me but before you build anything you must dry up your basement.

Just covering it over will not stop mold from growing whither you use metal or wood material.

Next, metal stud were not ment to be used as joists which is what the beams that support the floor are called.

If you were building in a dry basement, you would use "Pressure Treated" lumber that come in contact with the floor or outside walls. All studs and joists would need to be 16 inchs on center.

Concrete is porous and needs to be sealed to keep ground moisture from coming up through it and making the sub-flooring damp.

I don't know what kind of "Seepage" you have but they make a paint type sealer that will help for a short period of time if it is not to severe.

WOW
My question would be..
What is on the other side of the seeping wall? soil ,rock, rubble...
and how deep is this basement?
Knowing this may point towards a remedial suggestion from the AP gang

Sounds like you could make a real mess of it if you elevate a floor over this area without taking care of the moisture problem.

If you do decide to use the metal stud approach - make sure you put a vapor barrier down - plastic sheeting is the best approach. You will need to put the metal studs no further than 16" on center. Do not put them at 24". You should then use 3/4" plywood on top of that. I would actually prefer to see you use wolmanized lumber rather than metal studs - it has to be wolmanized if it is sitting on concrete. This is called using "sleepers" under a floor and it will give you a better surface and easier to work with surface to screw plywood to. If you do this, put the plastic on top of the sleepers before putting in plywood.

I wonder why you don't just put down vinyl tile? If you have a seepage problem I believe that this is the best approach especially if you consider it temporary. You wouldn't have to put in a floor structure and could just go straight onto the concrete.

You need a sump pump by the way. You should get a quote from a plumber to put one in. Typically that is the easy way to take care of seepage under a slab. It should cost around $800 - $1000 maybe more if you don't have an easy location to tie it in.

Seepage is minimal, we have a sump pump, as of right now I think we have scrapped the idea of the metal studs and are now considering the water channeling system. The basement is a "short" basement under 6'. So I will be looking at prices today for the channeling system and for vinyl tile & area rug. Thank you all so much for your help.

Even though the last post is almost two years old I will post a reply regardless to help any wayward surfers who happen across this thread. NEVER EVER EVER use plastic vapour barrier in basements. This mistake has been made for years by countless contractors across North America and probably around the world.

If you approach this problem from a building science perspective you would realize that plastic vapour barrier is meant for above grade walls that can dry from both sides. The exterior wall surface will dry by the sun and the air while the interior wall surface will dry from the conditioned interanl air. When we go below grade, in this case a basement, basic building science tells us that only one surface of the wall can ever be truly "dry"...the interior (assuming your basement is a conditioned space and not a crawl space). When a non-permeable material is used such as plasic vapour barrier, you are in essence trapping any and all moisture coming from the ground through your foundation wall. Some may argue that plastic on the concrete/block wall is fine but over time the moisture coming through the foundation will condense and pool on the exterior facing side of the plastic.

If you use a permeable material to form a thermal break you will never ever have an issue with mold and/or mildew. I only use two processes for finishing basement walls and floors:

1. Rigid foam insulation installed with foam board adhesive and taping the seams with tuck tape. This forms your thermal break and you can proceed with framing as usual. Depending on your local building code you may not need to insulate the wall cavities but it never hurts to add more insulation. DO NOT PUT A VAPOUR BARRIER ON THE WALL!

2. Use a spray foam. This is your safest approach to ensure no leaks or gaps. Again, frame the wall as normal and add batt insulation if required or wanted.

As for the floor, you can use the same approach but I suggest using a combination of dimple membrane with rigid foam insulatin on top, tape the seams, then lay your plywood on top. Fasten plywood through the rigid foam and dimple membrane using Tapcons or pre-caulked screws if you're concerned with moisture coming up through the screws.

Some people may argue that this sacrifices head-room but I'd much rather have a dry, mold-free floor with an inch less head-room. FYI: If you need to level your floor you can try one of two things with this approach:

1. Buy shims for the Dri-Core product. Great way to shim your floor under the dimple membrane.

2. Lay 2x sleepers over your rigid foam and shim before you lay your plywood.
Edited to remove ad.

This message has been edited. Last edited by: DorianGreyed,

It is not advisable to use a vapor barrier on basement walls below grade, but under the slab it is required by codes and it is advisable to place a vapor barrier under floor coverings like wood flooring. I do think it best to put the vapor barrier right on top of the slab (best under the slab), but the real problem in this whole post is something both WoW and I brought up - the moisture problem should be remedied rather than covered up.

The one sure way to have a mold problem is to encapsulate moisture problems.

I found this new posters website and think it's a great idea to spread this type of information, but be real... nobody was talking about walls.