Crawlspace Work
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I ended up doing a bunch of work in my crawlspace, so I documented it here.

Structural Improvements

The house was definitely "builder grade" when it was built, and that included the floors. The floor joists span about 8' per section and they are 2x6 (not a typo) joists set on 24" centers (again, not a typo) using a single layer of 5/'8" plywood (seriously!) over them. The plywood is glued and stapled (!) down, and a number of the staples had completely missed their intended joists. As a result, the floors we squeaky and bouncy, to put it mildly.

The solution was to improve the rigidity of the entire system and provide more support in any trouble areas, such as long plywood seams in key areas.

  •  Sister any weak or heavily loaded joists using glue and nails to join them together.
  •  Install flitch plates (aka, pieces of metal between a pair of sistered joists) on any problem areas. (Word to the wise: If you want to search on this to learn more, search only on the phrase "flitch plate" or you will find many sites devoted to a less than savory slang term that describes something you do not want to learn about... I need mental bleach...)
  •  Install "mid-span" joists (aka, half way between two existing joints) any place where sisters and flitch plates would not work
  •  Install blocking under any weak areas of plywood to transfer the load to the joists and stiffen the floor in those areas.
  •  Shim any joists and bracing that was not making solid contact with the main support beams or the floor.
  •  Put in a heavy coat of construction adhesive any where that new wood was installed, particularly on the underside of the floor.
  •  Install Squeek No More screws in every carpeted area of the house to ensure that the plywood was completely secured to the joists and any bracing. This is one of those products that may net a raised eyebrow at first, but I found that it really works well when installed properly. See my review on for more details.
  •  Have closed cell spray foam insulation installed in the entire crawlspace to increase rigidity, tie the system together as one piece, and add some insulation. The floors were originally uninuslated.

Doing all of this tremendously increased the rigidity of the floor system and made the house virtually squeak free. It was incredibly hard work. I know my crawlspace entirely too well after doing all of this. :-)

This is the pile of scraps from the lumber we cut. I was originally going to go with fiberglass insulation for the floors and I furred them down 4" to use deeper insulation. Then I researched spray foam insulation and went with that. All those furring strips were not needed. :-( Lots of 2x2 scraps...

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These were for installing the Squeek No More screws. We had to wrap up mid-way through the hall one evening, and we had to measure where the last screw was to be able to find it again later and continue. Once you snap them off, you cannot find them again.

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As part of the above work, I went with closed cell spray foam insulation in the entire crawlspace at an R30 value. I also had the HVAC ducts sealed and sprayed with closed cell insulation to help with heating/cooling costs, as well as noise.

These are the various valves in the plumbing system and related areas. I needed to ensure the pipes were in the middle of the insulation stack so they didn't freeze on cold winter nights, but still have access to the valves for service.

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The solution was to build boxes around them that have insulated lids/access covers, and then have the spray foam sprayed around the boxes. it worked like a charm and was reasonable cheap and easy to do. There ended up being four access boxes.

  •  One for the icemaker valve
  •  One for the cold water line drain valve
  •  One for the backflow prevention device along with it's associated test ports and shutoff valves.
  •  One for the exterior shutoff valves (there are 5 of them in a single manifold arrangement, one for each thing that I feed, plus a spare for future expansion)

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The previous owner had left a brand new roll of duct insulation in the crawlspace, presumably to insulate the ducts with at some point. Since I went with spray foam, I didn't need this and I gave it to a friend who could use it.

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These are the folks who have done all of my spray foam work, and will do more in my master bathroom when I get to that. Eastside Insulation is, simply put, the folks to call for all of your insulation needs. They do great work, have great prices compared to anyone else I could find in my area, and I wholeheartedly recommend them to everyone I know. If you want spray foam installed in your house, you need to call them now. Seriously. Stop reading and go call them. Now. :-) They were pros, and did a great job and the improvement was immediately noticeable. The floors are quieter, the house is tighter (fewer drafts), and there is less noise coming in from outside. Closed cell spray foam costs more than fiberglass or even open celled foam, but it is well worth the money in my opinion.

They did a great job at my house; everything from showing up on time, to putting plastic down on everything to ensure no mess, and cleaning up everything after they were done. Had I not been home, I would never known they had been there except for the fact that my house was now quieter and better insulated. They were also super courteous and helpful throughout the entire project. I had some specific requirements for how I worked this around my work on various projects, and they got it done perfectly.

One thing to be aware of is that foam does have a mild "sweet smell" right after it's sprayed, so plan on airing out the house after you get a job like this done. I have a very sensitive nose, so I smelled it for the first day or two, but it was not a problem.

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This is one of the Eastside Insulation guys in action spraying the floor under the master bedroom. It was very cool to watch the foam rise and cover everything, but I couldn't be down there while they sprayed without full breathing gear. The foam does outgas for a few seconds, and you need to be protected from that. After that, there is nothing else problematic. This picture was taken by me leaning in the access hole and snapping a cool picture for fun.

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Page last updated 06/24/2012 10:16:27 PM