Humidity in old basement

[Wrasse Man]

Hi all,

We are finalizing a deal on our new house! Yippie! Anyway, when we move in, I would like to relocate my sump to the basement. The only problem I can think of, other than the basement is ~5' tall, and I am close to 6', is humidity. The basement does not have any windows. I am concerned about accumulating humidity. You access the basement via a trap-door in the mud room, so I don't think leaving the door open will be much of an option.
Is there a way to keep the humidity under check, or is this something I should even worry about? I don't want to grow mushrooms down there
The walls and steps are all poured cement, and the ceiling is wood, which is the subfloor/original floor for the living room.
Do you think coating the walls and ceiling of the basement with Thompsons or some other water protectant will help?
Here is another reason for my concern: the house is a 102 yr old farm house, and is possibly one of the oldest houses in our county. I don't want to cause the living room floor to collapse!

Any ideas?

[Doug1]

sealing the underside of the floor is probably good idea, any way to draw house air thr and vent to outside.
Also you may need to think about a dehumidifier

[asmith]

I agree that the Thompsons sealer would be a good idea. You might also paint the underside of the floor with a good quality latex paint. I would also suggest a dehumidifier if you can't find a way to vent the basement.

Congrats on the new house. We bought our first home in July.

Andrew

[Minnreefer]

Before moving in I would paint the entire basement with some paint, that will help keep things clean and to see if/ where you may have a problem. I would also strongly suggest a good dehumidifier, because a basement will draw a lot of humidity in the summer. I would also recomend buying a few fans for air movement around the floor, a 2-5 MPH air movement will reduce/ stop any mold/mildew growth. I assume that it has a good solid block/stone foundation but you might be able to drill 2 4"holes for some type of venting for the basement.

HTH
Congrats on the purchase.

Jon

[mrlimpet]

Hello Wrasse Man

I too would recommend a good dehumidifier for your basement. Most of my tanks are downstairs and my basement would become a damp, moldy dungeon without one. I would also suggest using a floor jack or two to support your aquarium from below if your concerned about the weight.

Welcome to home ownership.

mrlimpet

[FishDaddy]

Congratulations on the new home, Wrasse Man!!!

There is a specific product for coating floor joists and the underside of flooring in basements/crawl space. I can't for the life of me remember the name of the product but a local home remodeling co. should be able to tell you.
Painting the underside of the floor might not be a good idea as moisture can penetrate under the paint, causing flaking which could wind up in the refugium/sump.

I'd be willing to bet that the subfloor is solid wood, laid diagonally, with wood flooring on top of that, and floor joists that would support a Sherman Tank!!! They don't build 'em like that anymore!

Dick

[Wrasse Man]

Thanks for the suggestions all!

I was planning on supporting the floor underneath the aquarium. I found out last night that there is a possibility that the 'subfloor' right now is the original pine or fir plank floor with the carpet installed directly to it. That means that the tank may be taken down and stored in the out building for a few months, so we can look at pulling the carpet and refinishing the original floor. I think that would be a great time to waterproof the entire joist and plank structure to make sure it is covered. Luckily we found an inspector in our area who is an old-house buff, so we should be able to find all of this out on Saturday.

Fishdaddy: You are right! The joists are about as thick as my thigh. The one thing we noticed about the house is that the floor doesn't 'move' when you walk on it. It feels like it is sitting on a concrete slab, not wood joists.

[Minnreefer]

I am sure that I don't need to tell you this but take your time and plan everything out as well as posible. A little more time now may mean a lot less worry/headaches in the future.

Good luck

Jon

[Peter_]

Originally posted by Wrasse Man
I don't want to grow mushrooms down there.

My hand is growing...write that down.