New Bathroom In Basement - Remodeling - DIY Chatroom Home Improvement Forum


Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Remodeling

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Display Modes
Old 01-11-2010, 10:14 PM   #1
Newbie
 
Join Date: Jan 2010
Location: oregon
Posts: 3
Rewards Points: 10
Default

new bathroom in basement


I have a partially finished basement in a 50year old house, I am putting in a bathroom. The walls are poured concrete with sill plate and wood framing on top. The walls appear to be waterproofed and painted. I do not have issues with water leakage or anything. One side of the new bathroom will be 2x4 framing along the concrete wall. Should I insulate this space along the concrete wall? Should I use a vapor barrier? I have worked in houses with finished basements with vapor barrier behind drywall, and they were moldy, very moldy. Any suggestions?

Advertisement

jhaug is offline   Reply With Quote
Old 01-12-2010, 12:10 AM   #2
Newbie
 
Join Date: Jan 2010
Location: oregon
Posts: 3
Rewards Points: 10
Default

new bathroom in basement


I also plan on putting down ceramic or porcelain tile on the concrete floor, do I need to seal the concrete first?

Advertisement

jhaug is offline   Reply With Quote
Old 01-15-2010, 04:28 PM   #3
Newbie
 
Join Date: Dec 2009
Posts: 12
Rewards Points: 10
Default

new bathroom in basement


I'm currently remodeling my basement and here is what I have learned:

Walls:

I would put polystryene foam board on the walls, it acts as a vapor barrier and insulate as well. The thickness of the foam board determines the insulating value (R value). I live in southern illinois and am using 3/4" on my foundation walls (biggest I had access to that still had a t&groove for better interlocking) Use a house wrap tape (Tyvek tape) on the seams where the foam board meets. Now you could put fiberglass batting in b/w the studs for even better comfort and with no worry about mold issues.

Floor:
It would not hurt to seal it. I had to lay down some self leveling concrete. So I'd say make sure your floor is level before you seal it, otherwise you'll seal it 2x.
rdtour is offline   Reply With Quote
Old 01-15-2010, 05:07 PM   #4
Remodeling Contractor
 
Join Date: Dec 2008
Location: Sandy Hook, CT
Posts: 3,590
Rewards Points: 2,000
Default

new bathroom in basement


Spray foam for the walls is the best way. But if too costly -- you need at least 2" rigid foam to act as a capillary break to prevent condensation from warm basement air hitting a cold basement wall. All seams to be taped and all gaps to be filled with spray foam. Then a 1/2" minimum air space between the stud wall and the foam board. fill this with kraft faced insulation batts. The sole plate must be pressure treated and use sill insulation as a capillary break under it to prevent moisture wicking into the wall cavity. No poly vapor barrier. In the summer the air moves into the room. In the winter it will move out. Any trapped moisture can dissapate in the air space provided.
Bob Mariani is offline   Reply With Quote
Old 01-15-2010, 06:43 PM   #5
Registered User
 
Join Date: Mar 2009
Posts: 10,007
Rewards Points: 2,080
Default

new bathroom in basement


I agree with the others on foam, this from Building Science: This means limiting extruded polystyrene insulation to less than 1-inch thickness for walls (more than 1 inch thick and they do not breathe sufficiently) and making sure that the rigid insulation is not faced with polypropylene skins or foil facings. From: http://www.buildingscience.com/docum...gs?full_view=1

And the craft paper facing if in a cold climate:
The greater the permeance the greater the inward drying and therefore the lower the risk of excessive moisture accumulation. However, in cold climates or buildings with high interior relative humidity during cold weather, the upper portion of a basement wall may become cold enough that a vapour permeable insulation will allow a damaging amount of outward diffusion during cold weather. A semi-permeable vapour retarder or foam or a supplemental layer exterior insulation can be used in these situations. Up to two inches of unfaced extruded polystyrene (R-10), four inches of unfaced expanded polystyrene (R-15), three inches of closed cell medium density spray polyurethane foam (R-18) and ten inches of open cell low density spray foam (R-35) meet these permeability requirements. From: http://www.buildingscience.com/docum...ts?full_view=1


I wouldn't use an air space that may give a convective loop, lessening the value of the batts and spreading the moisture around rather than heading
directly inside if you had an air leak anywhere. You get an R-1 with 1-4" of air space. http://oikos.com/library/insulating_...lls/index.html You need fire-blocking every 10 lineal feet as well as the whole top of the stud walls.
Be safe, Gary
__________________
If any ads are present in my answer above, I do not condone/support/use the product or services listed, they are there against my permission.
Gary in WA is offline   Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Completing a roughed in basement bathroom Bob in St. Louis Plumbing 8 11-18-2011 01:12 PM
basement bathroom JED5000 Plumbing 8 05-02-2009 04:34 AM
Plumbing Help for New Basement Bathroom morphers82 Plumbing 2 03-14-2009 01:17 AM
Renovating basement bathroom???? Oldyota Plumbing 1 01-10-2009 08:51 AM
re-adding a basement bathroom jimmyfloyd Plumbing 4 11-10-2008 07:31 PM




Top of Page | View New Posts