# Shed/tiny house floor insulation



## Jm101 (May 20, 2012)

My fiancee and I are building a tiny house. We have cut a building pad, using heavy equipment, that has very good drainage. I laid in about 6" worth of pea gravel on the house site, about 3 yrds. I am using cinder blocks that are notched for 4x6 skids to sit in. I am working for a local saw mill to get lumber, so the skids are high quality heartwood cedar. So with the gravel, cinder blocks, and skids the floor joists will be ~18" above grade. 

So my question is should be worried about using fiberglass insulation? I have been looking into a few options; 1 simply use hardware cloth for critter proofing, and put in fiberglass and not worry about it; or 2 install pressure treated plywood between the skids and the subfloor to protect the insulation and critter proof the structure; or 3 use hardware cloth for critter proofing then use a foil faced rigid insulation on the bottom with an air gap then either more rigid insulation or fiber glass. I apologize for the run-on. 

The house is in the foot hills of CA. Cost is a paramount consideration, however, we don't want issues down the road. I am not convinced I will have a problem if I just use hardware cloth and fiberglass because of all the efforts to get water away from the structure already in place. Should I be worried about splash back 18" above grade?

Thanks in advance,
Mica


----------



## Jm101 (May 20, 2012)

I am going to document the house build here.

I have decided to go with hardware mesh on the bottom between the skids and the floor joists. Then a layer of rigid board to help with water intrusion from below and support insulation above. Then fill up the space between the floor joists with "green fiber" loose fill insulation. I am figuring on loose fill because I have full dimension 2x6 floor joists 12" on center, so I only have a 10" gap between joists. I haven't found any insulation for that type of application.
In order from the ground up: 4"-6" pea gravel on a well drained site; bond beam blocks supporting heartwood cedar 4"x6" skids; a layer of hardware cloth under the floor joists; 2x6 joists; rigid board dropped in between the joists; install some 1x2 segments nailed into the joists, then screw the rigid board to the 1x2 from underneath to prevent the rigid board from sagging; fill the gaps between the rigid board and the subfloor with expanding foam insulation; the remaining space will be filled with the loose fill then the floor joists will be covered with 1x8 boards.


----------

