recommendations for resolving condensation problems in my crawlspace include: convert from open to closed crawlspace, install dehumidifier, cover walls and ground with plastic and use icynene instead of fiberglass on the the floor above the crawlspace.I live in the southeast. Has anyone had experience in resolving moisture/mold problems by taking this action? The cost is estimated to be $15,000!!
Although you can convert to a 'closed' crawlspace, converting to a 'closed' crawlspace requires no 1vents to be present, 2an approved vapor barrier over the soil, and 3insulation to be applied on the crawlspace walls, and 4 the area to be supplied with conditioned air.
Otherwise, the only approved method of having a closed crawlspace is for a vapor barrier to be applied over the soil and the crawlspace to be mechanically vented.
Even for moderatley large crawlspaces, it should cost no more than $2-$3000 to create a closed crawlspace that works as designed.
the proposal for my crawlspace (1400 sq ft) was broken down as follows: 1) remove fiberglass insulation in crawlspace and install icynene spray in subfloor= $4,480 2) install dehumidifier, pump and pad and ducts to supply air to all corners of crawlspace= $1,300 3) close off foundation vents with foam board inside and install vent covers on outside of those= $350 4) install the "Healthy Crawlspace Encapsulation system" for entire crawlspace(wall/peirs/floor)= $6,126
Your design is for a mechanically vented system to create a closed crawlspace. This is done by supplying conditioned air to the crawlspace and sealing the vents.
The problem is that for this design to work, by building code, the insulation needs to be on the crawlspace walls, not in the subfloor.
Supplying conditioned air to the crawlspace without the walls being insulated completely defeats the purpose of this design.
The entire idea of having a closed crawlspace is predicated on this space being conditioned. A 'conditioned' space means a space that is kept at above 50F in winter or below 85F in summer. But in order to create this conditioned space, it means the crawlspace walls need to be insulated.
If you insulate the crawlspace ceiling, then close the vents and add mechanical ventilation without insulating the wall, you actually create an area that is less energy efficient and can contribute to your on going problems.
It might help to know in what state you are located, but your deisgn is not an approved design by building codes, is far more exepnsive than necessary, and frankly won't work.
You need additional professional opinions, but the design as offered by your contractor does not jive with accepted building code methods.
Hello all, I have questions about the rating and best insulation (best R value)for my new home in Jacksonville Florida. This house is a concrete slab on grade, it has 2"x6" wood stud exterior walls with 1/2" wood sheeting and a house wrap over the sheeting a 1/2" to 3/4" air gap and then a 3-1/2" brick. On the inside we are required to fill all the holes drilled into the wood studs by the electricians and other subcontractors with fire caulking we are installing 5/8" fire cold sheetrock as a finish on these 6" studs. My questions is what is the best way to insulate my house right? What are your thoughts about the different types of insulations? What about cellulose? Thanks, Ken
Originally posted by homebild: It might help to know in what state you are located, but your deisgn is not an approved design by building codes, is far more exepnsive than necessary, and frankly won't work.
This system will work, but in the winter it will use a significant amount of energy to dehumidify the crawlspace to the point where the humidity cannot reach dewpoint on the walls. As well, if the crawlspace ceiling is insulated, and they use unconditioned air for the supply, it shouldn't lose too much heat in the winter....
In the summer, you can't use outdoor air for dehumidification. In which case using conditioned air will reduce the amount of dehumidification that is necessary. Heat will definitely bleed in through the walls, but so what, it will get vented, as the mech system is not tied into the main system.
Generally you are right though - insulation on the walls & normal poly on the floor would cost FAR less, and use less energy.
But there are added costs: supplying conditioned air to the attic & venting it through the house, and fire protection (ignition barrier) for the insulation on the walls.
quote:
Originally posted by diamondKen: Hello all, I have questions about the rating and best insulation (best R value)for my new home in Jacksonville Florida... ...My questions is what is the best way to insulate my house right? What are your thoughts about the different types of insulations? What about cellulose? Thanks, Ken
Kenny maybe the best thing to do is start a new thread. The only people that will read this are people interested in crawlspaces...
