DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (
-   Building & Construction (
-   -   Couple basement subfloor questions (

ryanmcl 01-20-2013 09:05 PM

Couple basement subfloor questions
I'm getting ready to submit for permit and had a couple questions about the subfloor.

After i insulate the walls with 2" XPS I'm going to put 1" XPS on the floors. My questiosn are:

1. Do I frame direct on the XPS or do I put the Plywood down first and frame on top of that?

2. Should the subfloor extend to all parts of the basement? Specifically, storage areas, utility rooms, bath room?

3. How close should i get to my sump/furnace/drains?

4. Is there a bid difference in using 3/4" Advantec vs two layers of 1/2? I have seen people go both ways. Head room is not an issue.

5. How do i fix the stairs since the new floor will raise a couple inches?

Here is my latest floor plan if it helps at all.

Thanks for any and all help.

jklingel 01-21-2013 01:48 AM

ryan: first, where are you? second, what is your planned use for the floor you are insulating? (play room, workshop, etc).

whatever thickness you use, remember that an inch is not a great deal. if headroom is not a problem, two, 1" layers w/ staggered seams (all taped and spray foamed between gaps) is what i'd suggest (that depends somewhat on where you are, too). are you going to tapcon the plywood to the floor?

you mentioned framing; another sub-floor atop the rigid foam, or just interior walls? if just walls, i'd install 3/4" t&g ply and tapcon that to the floor, then build any walls atop that.

depending on what will be in the room, use rigid foam w/ sufficient psi for the job, remembering that the advertised psi on rigid foam is for (approx) 10% deflection, which is getting into the permanent deformation range. thus, us 3x-psi foam: ie, if you are going to have a large machine at one spot, and it will load up 10 psi, use 30 psi foam. vapor barrier on the floor first, then foam.

vinyl flooring can be problematic if you have any moisture in the slab, so something more vapor open would be safer. can you stub up the drains at all, using a smaller drain inside the old one?

oh'mike 01-21-2013 06:06 AM

Your location is needed for code advice----subfloors in a basement are uncommon and often are damaged by water----requiring ripping it all out---

I'll leave this for others---I do not like the idea because of water under the subfloor.

ryanmcl 01-21-2013 11:44 AM

I'm just noth of Chicago.

The basment is going to be multi purpose. Rec room, living room, bar, office, play room. I orgianlly planned on using a subfloor for the entie area.

For the rec room/livingroom/play area i was thinking engineered hardwood.

For the bar i wanted to do ceramic tile.

For the office i wanted carpet.

My main reason for the subfloor was to keep things warmer and get away from the "basment" feel.

oh'mike 01-21-2013 12:21 PM

Thick carpet pad and high quality carpet----heat mats under the tile---best quality mat under the engineered floor---and the subfloor could be omitted.

I know your area and have built many nice basements in homes like yours----the subfloor is not needed or recommended.

Just my opinion based on many years of building and restoring water damaged basements.

ryanmcl 01-21-2013 12:37 PM

Thanks Mike, if I won't lose too much warmth i dont might ommitting the subfloor.

Is this the type of mat you are refering to for under the tile?

Also- do you advise basebaord heaters?

oh'mike 01-21-2013 12:50 PM

Yes---Nu-heat has a good track record----and there are other tried and true brands---
Other members could guide you on best brands---

If you have forced air heat---Have a heating company come see if it has the capacity to condition your basement---most do---

I've never installed baseboard heat in a house with forced air---we always use the existing furnace and perhaps some extra duct work----

Heat mats can be used under carpet or even your engineered floor---

All times are GMT -5. The time now is 08:14 PM.

vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

Search Engine Friendly URLs by vBSEO 3.6.1