Insulating crawl space

jenoble99

I am considering insulating our crawl space as there is no insulation at all. I'm debating on which type and how to do this. Is the preference towards insulating the crawl space wall and with what? Or between the floor joists with batts and then also insulating the water pipes, etc. I already have a vapor barrier on the ground and the crawlspace is vented and dry. What are the thoughts of everyone out there? also, we have radiant ceiling heat if this makes a difference in how you would do it. The house was built in '64. Is crawl space insulation worth the effort?

Bob Mariani

insulated the floor joists with batt insulation as long as you are sure it is now dry. And yes.. insulate all plumbing lines with a fiberglass pipe insulation.

Wildie

Insulating the walls and headers is a better option, then the plumbing will be protected! All outside venting should be permanently closed off and the space conditioned for both heat and A/C. Most moisture that occurs in crawl spaces, arrives via outside vents!

jenoble99

The only issue with this is we don't have central heat, we have central A/C but our heat is via radiant ceiling heat.

Scuba_Dave

I had a similar situation & was instructed to insulate the outside walls & not the floor. I'd also insulate the pipes

Bob Mariani

A newer approach to crawlspaces is to seal the vents. Codes have not caught up but often these vents are sealed as soon as the crawlspace is dry.

From another site.
Q. I am building an addition over a 30-inch-high crawlspace. The local inspector has approved my plan to build a sealed crawlspace without ventilation. Should I install rigid foam insulation on the interior of the block walls, or should I insulate between the floor joists?
A. Howard Ferree, a licensed general contractor in the Asheville, N.C., area, responds: In almost all cases, I’d suggest installing the insulation between the floor joists. Unless you are located in a climate where the crawlspace needs to be heated to keep the pipes from freezing, you don’t want to heat and cool more space than necessary.
Although there is still some controversy about the best way to prevent crawlspace moisture problems, I’m now convinced that the most effective approach is to seal crawlspaces completely. Polyethylene should be installed across the crawlspace floor and should continue up the interior of the perimeter foundation walls, to form as complete a seal as possible.



My idea of the joists was due to the fact she is trying to keep the floor above warmer, not the crawlspace.

Wildie

If you have enough capacity in your electrical panel, a heater could be installed in the crawl space! It would help warm your feet!

Scuba_Dave

True, this depends upon location
My floor was actually already insulated
I opted to leave it & add the perimeter board insulation
My pipes were insulated & my heating ducts were insulated

If it's deep enough down the ground stays around 50-55
By adding the perimeter board it allows the crawl space to maintain a min heat in the winter

Wildie

Thata a valid point!

Equjumper

I live in Northern New York, and the floor of our crawlspace is dirt. We via Monitor heating. The pipes below the house are not insulated. Should we insulate our pipes, insulate and seal the crawlspace and also lay a vapor barrier over the ground? We are planning to start this project early fall.

Thurman

"To insulate crawlspaces or not". I think this is a question that will go on forever. I also believe it has a lot to do with what part of the county you are located in. As far as getting a crawlspace dry, this is my story: Standing and looking at my front yard, there is a negative elevation change of about a foot from right to left. There is also a negative elevation change from the right front corner to the back left corner of 28" in approximately 192 feet. Now, we are sitting on that famous S. GA. red clay soil which is actually really fine, ground up, course sand. Water will enter my yard at the right front corner and migrate through this clay to the back left hand corner, according to the Geologist in my area. I do know this, water will migrate through the concrete block of my house foundation and into my crawlspace. A small trench dug part way along the front inside wall of my foundation confirmed this. Another trench dug all along the front inside foundation wall and then along the eastern foundation wall will let water actually migrate to this lowest point and will puddle there. Therefore, there is a shallow trench all along my interior foundation wall, allowing water to migrate to the lowest point to a catch basin. At that point there is a small sump pump which will pump this water out. Sometimes it will be three to four days after a heavy rain when I see this water being pumped out. I also have a fan on a timer under my house to provide extra circulation. Yet, in my business I have to crawl under houses in my area that the dirt is as dry as a desert. Good Day, David