Basement Subfloor?

[PJ]

I don't know if this is the right group for this, so maybe someone can point me to a better one. We are going to be putting carpet in our basement (here in Denver, CO) over a typical concrete floor. We were wanting some insulation between the concrete and the carpet and had heard of some basement subfloor products. The two I've found so far are...

Delta-FL:

of those companies has a distributor near us in Colorado, so that made me wonder. Do people only put these products down if there is a basement water leak concern, and not for insulation like what we had in mind? Obviously in Colorado there's not much humidity, so I was just wondering if this product isn't considered "necessary" here. The other question I had is: Does a nice carpet and a thick pad provide enough insulation to keep one's feet from getting cold (our concrete basement floor is quite cold to the touch)?

Thanks for any advice, PJ

[gabriel]

If you do not get an answer, you could try alt.home.repair, they are pretty active in that group.

[j.b. miller]

The Dri-Core stuff looks real similar to some panels I've seen at Home Depot.If you don't have one nearby, you can 'make' the same thing by laying down a section of foundation wall 'bubble wrap' as I can it , then sheets of OSB.You could put a layer of say 1" waterproof insulation(extruded polystyrene) between the 'bubble wrap' and the OSB. Any decent yard will have both of these items.

hope this helps

Jay

[Ben]

A friend of mine installed the Delta product in their Basement here in Cincinnati OH. Their main concernt was water. They had a few small leak spots repaied before the remodel but they thought this was just extra protection. It worked nice. It allows and air flow inder the floor. I would think it would be a great insulator too. They covered it with OSB and then padding and carpet. Seems to be very nice. And not too expensive.

[Nate B]

"PJ"

I live up in Boulder. Just carpeted my basement with a typical pile kind of carpet. Carpet + pad seemed pretty adequate to me. Maybe you'd do this option if you wanted a thinner industrial type of carpet - but seems you'd be looking at a lot of work to your door bottoms and base trim. Might want to add that into your estimate. Way high overhead with questionable return, it seems, given our climate. I'm no connoisseur, but it seems as comfortable as I'd want it to be down there with just carpet + pad. I think ventilation and insulation are going to make a bigger difference in how cozy you feel.

- Nate

[doug houseman]

All 2000 sq feet of our basement has been done over the last 15 years . neither of the products you talked about existed then. So we created our own.

First cover all the interior concrete with a waterproofing product - do it well - ensure that any current cracks and holes are filled. Use an epoxy product - it will reduce the amount of chiseling you have to do.

For this to work long term you need a dry basement.

1) Paint all the wood with Kilz or a similar product that has a mildewcide in it. let them dry...paint all the sides. Keep a cup of it handy when you lay the wood to treat any cut edges.

2) using 1-1/2 inch thick pink or blue builders board and 2x4's - alternate so that you have a 2x4 laid flat against the wall then another at 2 feet on center and 4 feet on center - cut the builded board to fit in between. Do the whole floor this way. Do not worry about anchoring the material to the floor or the walls - gravity does a pretty good job, Go ahead and use the scrap pieces to fill in in the middle.

3) again paint the daylights out of the plywood or OSB and cover the 2x4's with the plywood - using galvenized or stainless screws to anchor the plywood to the 2x4's - ensure that you countersink the screws at least 1/8 of an inch.

4) Call the carpet guys.

I promise a warm and comfortable room (we have 2 kids bedrooms, and our family room in the basement here in Michigan - the floor is as warm downstairs as up.

WARNING - if you do not get the basement dry and the wood covered you will end up ripping it all out.

We run a dehumidifier hard prior to laying the floor to get most of the moisture out of the air and off the concrete.

Doug

[PJ]

Thanks for all the posts. The one by Nate (in Boulder, near me) made me realize that all my drywall and baseboard trim is already installed with the standard gap to the floor. Whatever subfloor product I installed, if I did, would have to be a certain distance away from the walls to avoid interference problems. That post also made me wonder how they put tack strips for the carpet on the concrete floor. I've definitely got some questions I need to run by a carpet installer.

Thanks for all the input, PJ

[Mike H.]

I am going to be installing the Dri-Core product in the next few weeks in my basement (750 sq. ft.). I live in Ottawa, Canada and the Home Depot does carry the product. It is a little pricey at $7(CDN) per 2'by2' panel. I researched other subfloor options but the main reason I chose this system was height. I am 6'3" and this floor is only 3/4" which is great with HVAC trunks and I-beams hanging under an 8 foot ceiling. The panels look easy to install, waterproof (including wood treatment), allow any water leakage to travel to lowest point and provide an air gap between floor and carpet/laminate. One of the 3 rooms is a home theatre room and will have kids laying on the floor so I wanted something warm. If your concrete is young do not paint, it will take a few years for it to breath.

Mike H.

[mttt]

Here, in Denver, also - and finished our basement last year. Basement is floating slab of concrete too. We've got a cheap pad over inexpensive Berber. It's fine. Much to my surprise as I was expecting it to be somewhere between "noticeable" and "uncomfortable." Nope. It's absolutely fine - summer and winter.

An R-11 blanket was on the walls already - so I left it there and just framed up to it. Also fine. There's a bedroom, a playroom, a craft room, a bathroom and a media room down there. Only the media room is chilly - but was easily remedied by a $35 Oil Heat heater from Lowes.

The hot water heater and furnace are in a separate room w/ a drain - so I'm not too concerned about a leak.

Discussed this w/ my builder and a subfloor would have increased the cost and decreased headroom down there.

Other consideration - radon mitigation system? Regardless of whether you believe in the problem or not - it is cheaper to get it installed before the basement is finished. My cost was $750.

[mttt]

But they did float (suspend) the walls, right??? Only the baseboard comes close to the slab?

[PJ]

Yes, these are floating walls. I believe the contractor set the baseboard trim to be a certain height (3/4" ?) off the floor, but it (and the walls) are definitely not connected to the floor.

[PJ]

Thanks for the feedback. We're definitely going with a thick pad and a thick, plush carpet. It's good to know that the extra expense and installation hassle of a subfloor is likely unnecessary.

I am suspecting that I'm also going to need to augment the heating in the main basement entertainment room (only one vent from the furnace heats the room) with some kind of portable heater. Does your oil heater not give off any harmful gases? I was thinking of going with some little electric unit, actually.

Thanks, PJ

[mttt]

The "Oil" unit I mentioned is Electric - but rather than hot coils and a fan - it heats up a radiator filled with oil. Looks like a little old-fashioned radiator. But will consume up to 1500 watts of current. Gives a much nicer, radiant warmth. My media room is about 15x15 and one of these $35 jobbies can heat it up to the mid 90's if set on high.

Basements don't take much - I leave it on, set to "low" and it's mid 70's in there.

Picked this one because it (supposedly) is about as child-safe as you can make a radiant heater.

I've got vents in all of the rooms, but my contractor [ picked "parsimoniously" :) ] had to really boggle up some duct work to get it into some rooms. There's just not enough oomph in the furnance and too much restriction in the flow to heat up the room.