Should I bother finishing a basement in an old house?

16 years ago

Hello all. I am new to this forum--usually I am over on Kitchens. I have been reading posts here trying to educate myself and will continue to do so, but since we are talking to to contractors already about finishing the basement I want to go ahead and ask opinions here.

Our house was built in 1910, and is outside Boston. It's a Victorian with a small footprint. Rubble foundation, and of course none of these exterior vapor barriers and such. We do have exterior french drains and a sump pump; we have had some water in the past but I think has often been from gutter issues (which of course could occur again). We are currently having the foundation repointed (interior now, and xterior when it's warm enough). The main issue is that it is COLD down there--40 degrees today (outside temp was around freezing, so not much different). What is going on here? Where do we need to insulate?

Ideally we do want to use it as a playroom--it is semi-finished now (ceiling, some finished closets) but needs a WARM floor, walls, and yes WARMTH. We would waterproof (vapor barrier on the inside walls and a trough/drain cut around the perimeter)and then install some kind of vapor-barrier flooring and insulated walls (not sure what kind of insulation,I am overwhelmed at this point). HOwever, my husband thinks the project is basically hopeless because of the age of the house, type of foundation, etc. Is it? Please advise before we commit to $$. Thank you!!

Featured Answer

homebound

16 years ago

How much $$ are you willing to commit?

I finished our basement (1947 home). The basement was freezing also, and it was greatly remedied by finding and sealing air gaps between the house and the foundation wall. I tucked openings with copper mesh, then sealed with foam. Over that I insulated the rim joist (I used 2" solid foam, followed by spray foam to fill in the gaps. All this sealing did wonders, even with no heat, bringing the basement temp up to 55 on the coldest days. (We're in VA, near DC) So I would say to do that regardless of anything else you do.

Next add solid core insulation on the walls - glue it right on, and tape the seams. That'll take care of the vapor barrier issues, as well. Next frame in, and add extra insulation.

Now, if water is an issue, that really has to be addressed. Gutter problems? Perhaps add a second downspout - I did that to deal with the yearly "monsoon" rains, as well as keep the gutters cleaned...so now I have the gutters pitched to both ends. Made a huge difference for us.

As for having a warm floor, lot's of different opinions on that. We opted to paint the concrete and use area rugs. BTW, I installed baseboard heat on it's own zone (we have hot water radiators upstairs). So far so good. It's very pleasant down there (and "snug" in the winter months).

If it's an old house, you probably have low ceilings down there. If so, keep in mind that stuff like dricore takes away a couple more inches in height by the time you're through. We just didn't have the height for that.

One last thing, I helped finish a basement for a friend in a 100+ yr old home to use as a playroom. They didn't even add heat, yet they still think it was the right decision, having gotten lots of use out of it for the kids.

Sort by:Oldest

Comments (6)

hollylh
Original Author
16 years ago
Homebound--thank you so much--this is very helpful. I do think if it were warm and snug down there it would get a lot of use. One thing I can't decide is whether to have it professionally waterproofed or not. There is not a lot of seepage down the walls or anything--actually none that I have ever noticed--and maybe a little bit from the concrete floor. When we have had water before, it has been from gutter problems and/or water coming in the foundation; hopefully having the foundaation repointed will take care of that. I feel like the absolute safest thing would be to waterproof before we did the rest of the finishing, but it would be like a 10K insurance policy and of course I would rather not spend the 10K. When we have had water before, the worst flood has been I think about 3-4 inches deep (actually the worst one was when we were out of town and our saintly neighbors cleaned it up for us; our sump pump failed that time and I think it was maybe it was deeper, but I didn't see it). So I am weighing what the cost of the damage to a finished basement would be if we did have another bad flood vs. cost of waterproofing. What do you think?

I am also a little confused about this question of a single vs. a double vapor barrier. I am reading the building science website but it is pretty technical for the likes of me. I am glad to hear you think the single is OK.

Our ceiling is 6'10". We used to have carpet with a pad but it flooded one too many times and we got rid of the pad; I think everyone would prefer a more padded surface and I would feel better if there were a little space between the floor and carpet in case of water. I guess I would be willing to give up a couple inches (although I don't know what code is here).

Thanks again!
Related Professionals
Brownsville General Contractors · Coshocton General Contractors · Gainesville General Contractors · Genesee General Contractors · Leavenworth General Contractors · Milford General Contractors · Palm River-Clair Mel General Contractors · Baltimore Architects & Building Designers · Glens Falls Architects & Building Designers · Palos Verdes Estates Architects & Building Designers · Apple Valley Flooring Contractors · Costa Mesa Flooring Contractors · Easton Flooring Contractors · Englewood Flooring Contractors · Everett Flooring Contractors
Brewbeer
16 years ago
If the foundation is in real good condition and has no leaks, then consider sprayed-on closed cell foam. This will insulate real well and be a good barrier to moisture migration.

You will need to install a back-up to the sump pump. Consider a second sump pump, and a municipal water supply powered redundant back-up pump in case of power failure.

Hopefully worthy will weigh in with some of his excellent input on this subject.
homebound
16 years ago
You want just one moisture barrier, which is provided by the foam. Spray-on is "seamless" (no gaps), but I don't know how expensive that is. I also agree that you need a back-up sump pump. BTW, how's your grading? Hopefully it's sloped away from the foundation, and you have gutter extenders, at least for a couple feet. (BTW, I'm not a fan of submerging the gutter outflow in that black corrugated stuff - just one more thing to clog...and maybe even breed mosquitoes near the end.)
hollylh
Original Author
16 years ago
I don't know if this foundation is in good enough condition...it will be the best we can do with the repointing but since it's 100 years old and stone/rubble to begin with there is a very good chance there will be leaks again down the road, I guess...what if the insulation were sprayed on the inside of the new walls and there was a small gap between the wall and foundation? If the insulation were sprayed right on the foundation, would it expand and crack the pointing?

(Homebound--I forgot to say earlier about the solid core insulation--I couldn't glue it right on the foundation walls because they are quite rough.)

Brewbeer, thank you for the info about pumps...we have an emergency battery backup but maybe a second one is a good idea.

Thank you and keep the advice coming!
homebound
16 years ago
No need to worry about any gaps underneath, and no, the spray-on won't crack anything.