Installing insulation between Metal Floor joists in crawlspace
I recently had to flip insulation in a crawlspace that has metal floor joists that are spaced 24 inches on center. As you know if you have installed insulation before with wood floor joists, the metal straps are 23 1/2 inches long and do hold ok with wood floor joists. With metal floor joists, it is much different, nothing for the metal straps to hold on to and the straps are not long enough to hold. So after looking through the internet for ideas, nothing came up, so I had to get creative and make something work. Well the answer was 1/2 inch plastic drip tube that is used for landscaping irrigation for plants. I went to the local home improvement store and looked around for material that was 1) strong enough to hold insulation in place 2) not expensive for the amount I needed and 3) would last forever in a crawlspace with the conditions of it. I found the plastic drip tube in the plumbing section at a length of 500 feet for a price of $40.00, YES $40.00!!! That is a bargain when you think about the price of the metal straps ($18 a box of 100). The metal joists have holes already in them for plumbing and electrical lines/wires to pass through, so I used the holes to install the drip tube. The holes are 1in dia., the drip tube is 1/2 inch dia. The spacing between the joists is 24 inches on center so you cut the drip tube at a length of at least 28-30 inches. I used a pair of siding cutters to cut the tub, you can also use a PVC pipe cutter or a razor knife. You cut it long so you have enough length to have them hold together. You first will install one side under the insulation to hold it up, in the next joist bay, you install the next tube into the same hole where the first tube is installed, this will lock the tubes into place so they won't slip out, they will fit, they are only 1/2 inch dia each. Keep doing this on the rest of the floor joists. You can turn the tubes so the curve of the tube pushes up on the insulation, it's not so much to compress the insulation, just more support.
The good thing about using this material is that they will never rust, rot, or corrode. They will also not bend and get damaged, they will stay flexible to a point, but stiff enough to hold the insulation in place.
This technique saved me tons of time and aggravation trying to figure a way to keep the insulation in place. The only reason I had to do this was due to the previous home owner or contractor installing the insulation with the paper side down and they stapled the insulation in place to the subfloor. This is not the proper way to install insulation. The paper also states that it is flammable, don't leave exposed to heat source, and you always install the vapor barrier toward the warm side of the house. In most states it is toward the living space.
Hopefully this will help someone out when they run into this issue. I know I will use it again if I come across these metal joists again.
I have attached photos of the tubes used and the technique. Tubes holding up the insulation Tubes locked together through the 1 inch holes in the floor joists Metal joists and spacing of 24 inches, holes already in them.
Hi folks. So I’ve got an enclosed outside porch that I’m repairing and have the opportunity to insulate the floor which is otherwise exposed and very cold limiting the utility of this porch despite having insulated windows, walls and electric baseboard.the porch is about 8X15’, and the floor is 5/4 meranti. We built this porch on an old poured concrete porch, resting 2X6 joists on top of the old concrete floor. I’m restoring the outer face of this floor/deck that the porch sits on, so the outside ends of the resulting 6X16 X 8’ cavities - meranti top, 2X6 sides and concrete bottom, are open temporarily. My thought is to spray expanding foam insulation in the channels and let it seal and fill the void. I don’t think that stuffing the channel with Fiberglas is practical and tho I will seal it back up that also seems like a home to pests. I’ve contacted a couple contractors and waiting to meet, but is this the right approach and can I do this myself with rented equipment? I’m very capable but informant in this space! Thx as always Read More
Our main water shut off valve is located in a closed in area underneath our house, which is itself exposed. The house is an A-Frame that sits on piers. The walls that enclose the space in which the pipes leading into the house are situated are pretty thin and so they don't provide much in the way of protection. The house is in Northern Western Virginia and so it can get pretty cold in the winter (dropping into the teens on occasion, but usually into the upper 20s at night at the coldest, but 30s regularly). There is a floor heater mounted on the wall of the small room which will keep the space warm, but the heater gets pretty warm and I worry about it being a fire hazard, particularly with some of the exposed paper faced insulation. I am trying to figure out the best way to keep the pipes from freezing.
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[*]Would a cover on the heater work, so as to provide a barrier between it and potentially flammable elements around it?
[*]Would it be better to use some sort of [url=https://www.amazon.com/Frost-King-HC3A-Automatic-Electric/dp/B000IKSQ8U/ref=sr_1_5?dchild=1&keywords=electric+heat+tape+for+pipes&qid=1634341117&sr=8-5]electric heat cables[/url] and wrap it around the pipe? If so, should I enclose that with some sort of [url=https://www.amazon.com/gp/product/B000BQSMCG/ref=ppx_yo_dt_b_asin_title_o04_s01?ie=UTF8&psc=1]fiberglass wrap[/url], or just leave it as is?
[*]Is there a better solution?
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Thanks for any tips. Attaching photos of the space to help situate your thinking.
Todd
[img]https://cimg5.ibsrv.net/gimg/www.doityourselft.com-vbulletin/498x1080/pipes_233d11d6979f0a8b0910852a253f9479f88247dd.jpg[/img]
[img]https://cimg1.ibsrv.net/gimg/www.doityourselft.com-vbulletin/2000x922/heater__318af8beb32f2ee0b235f5d873c613fc70d33fe5.jpg[/img]
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