Mr. Inspector
SAWHORSE
Doing alterations. Have a 15'x10' 18" high crawl space. My inspector said I have to vent it. If I put plastic down and fill the crawl space completely with insulation do I still need to vent it?
No......you can replace the floor system in 10 years instead!....The problem that the ventillation is trying to address is the removal of water vapor from the space...If you get some condensation (which you will) if it dries, no biggie, if it can't because there is nowhere for it to go it sits and rots.....That is why code requires ventilation...Rick18071 said:Doing alterations. Have a 15'x10' 18" high crawl space. My inspector said I have to vent it. If I put plastic down and fill the crawl space completely with insulation do I still need to vent it?
Take a look at IRC 408.3 for alternativesRick18071 said:Doing alterations. Have a 15'x10' 18" high crawl space. My inspector said I have to vent it. If I put plastic down and fill the crawl space completely with insulation do I still need to vent it?
If he installs a vapour barrier at the ground level and seals it well the only moisture will be migrating through the floor system from the building above. We have them all the time up here and don't see any problems with rotting. It also provides a much warmer floor.steveray said:No......you can replace the floor system in 10 years instead!....The problem that the ventillation is trying to address is the removal of water vapor from the space...If you get some condensation (which you will) if it dries, no biggie, if it can't because there is nowhere for it to go it sits and rots.....That is why code requires ventilation...
As long as the ground is covered with vapor barrier as noted in 408.3 there is no ventilation requirementRick18071 said:How can you ventilte this floor if there realy is no space? The 18" crawl space is all filled in with insulation. Is it still considered "under floor space" if there is no space? In the other half of this same room there there is a concret slab which was part of a garage at a higher elevation. To make my floor level I have 2x6 joists siting on plastic that is right on the concret slab with bats of insulation between them. How do I vent this under floor space? Or is this not considered a "under floor space"
That would not change the fact for pressure treated or decay resistant wood and impermeable insulation.Rick18071 said:What do you suggest I do. Fill the crawl space with dirt and cover with plastic?
Sorry to hi-jack the thread. I have a duplex I am about to go do a final inspection on. Crawl consists of ICF walls, closed cell spray foam rim joist, R19 batts in floor joists, nicely installed reinf 6 mil poly vapor barrier with radon reduction system underneath. NO ventilation to crawlspace. Thinking I need to at least make him put a floor register in somewhere to create a little air movement. Keeping in mind that it is dry as a bone here with little chance of the relative humidity ever getting above 30-40% down there.Gregg Harris said:As long as the ground is covered with vapor barrier as noted in 408.3 there is no ventilation requirement
408.3 any of 2.1--2.2-- or 2.3Mr.Inspector said:Sorry to hi-jack the thread. I have a duplex I am about to go do a final inspection on. Crawl consists of ICF walls, closed cell spray foam rim joist, R19 batts in floor joists, nicely installed reinf 6 mil poly vapor barrier with radon reduction system underneath. NO ventilation to crawlspace. Thinking I need to at least make him put a floor register in somewhere to create a little air movement. Keeping in mind that it is dry as a bone here with little chance of the relative humidity ever getting above 30-40% down there.Any comments