INSULATING CRAWLSPACE

[Henz]

I HAVE AN OLD HOUSE WITH AN UNISLULATED FLOOR (TOUNG AND GROOVE HARD PINE) AND THE SUBFLOOR IS THE OLD PLANKING STYLE.. I AM GONNA USE RIGID FOAM TO INSULATE IT..WHAT SHOULD I DO TO INSULATE THE VENTS FROM THE FURNACE THAT GO THROUGH THE FLOOR?

 

[kevinmoelk]

Are these vents on the supply side or the return side?

-Kevin

 

[Henz]

most on the supply, two on the return.. the person who installed them did a real chitty job of fitting the aluminum duct to the cut out section of floor that is for sure..I am always getting a cold draft coming from the return when I have my blower going on the woodstove.

 

[kevinmoelk]

On the returns I suppose you could use spray foam since they only carry cold air. However, this will make future servicing difficult. On the supply sides I'm not so sure. On my house I'm using aluminum tape to seal up all the seams, and where the supply comes out into the room I'm stuffing little bits of fiberglass insulation (just enough to stop drafts) in the gap between the edge of the drywall and the supply vent, then making sure I fit the cover nice and tight.

-Kevin

 

[Henz]

THATS A GOOD IDEA USING THAT ALUMINUM TAPE..I WILL DO THAT..BASICALLY STUFF IN SOME FIBERGLASS IN THE GAPS, MAYBE SO DOME ADDITIONAL SCREWING IN TO SEAT BETTER AND THEN FINISH IT OFF WITH ALUMINUM TAPE. GOOD PLAN!

 

[Highbeam]

I was told that the tongue and groove planking used to make the subfloor above the crawlspace was to be left uninsulated in order to allow it to breathe. The floor below me is the planking and has no insulation. Is there really any trouble with insulating/sealing the wood off?

 

[Henz]

BEATS ME MAN..ITS A FUNNY THING..THE KITCHEN FLOOR THAT I HAVE IS OVER A CRAWL SPACE AND HAS NO INSULATION AND IS COLD AS HELL. THE SEAMS ARE MUCH MORE PROMINENT THAN THE FLOOR OVER MY OLD BASEMENT WITH REALLY NO SEAMS SHOWING..

 

[kevinmoelk]

Adirondack, turn off your caps, that's considered yelling.

Highbeam and Adirondack, the topic of insulating the floor has a thread around here somewhere. There are ways Highbeam, let me know if you don't find the thread and I can walk you through it. Every situation is different, so how you insulate your floor requires some consideration, but certainly it can be done.

-Kevin

 

[elkimmeg]

Insulating the floor with ridgid HighR styrofoam is one way but what about under the cabinets cold air is going to escape under there it would be like doing 1/2 the job What about filling the joist bays with fiberglass? tyhen seal it up with thin ply wood or panneling.. Another way would to fill in the bays underneath with strips of the ridgid syyrofoam at least 2" this or double layer 1"

To insluate your ducts R6.0 fiberglass 2" thick is the besty way to go wrapping it around and staple seam it that HVAC tape does not hold up one can use it to hold things together till
staplimg is done. One also can wrqp the boot flanges for additional protection this also helps for condinsation in the summer on the AC cycle and insulate the returns as well especially if you have AC.. How high above the ground is the crawl space? If you have not done it yet I suggest you install 4 or 6 mill plastic on the ground to prevent moisture from enterning any structure or insulation above it is ok to hole it in place with stones or bricks