mobilehomerepair.com

Hello all,

New member here.

I ran across your site through google and I ma glad I did.

I have a roof problem. Old mh with the metal roof that is flat in several areas. The trusses are broken. I read the posts on using 3/8 plywood to fix the problem. I have about 15 trusses that I need to fix.

On a few there was a metal support holding the upper board and the lower board together. The metal bent and the top of the truss fell and let the roof drop. I replaced the stamped metal braces with some short 2X4s and it raised the roof quite a bit. Almost perfect but there is still a little dip in one area. When I push up on the metal it goes up with a pop. Only an inch or two. There is a slight dip looking at the roof from the top.

I have 2 questions. 1.) Does the repair manual cover rebuilding the roof trusses with plywood? Any photos?

2.) I got the impression from your site, I thought, that I could slide a narrow piece of 3/8 plywood about the truss to raise the roof. I was unable to locate that info again but I'm sure I saw it somewhere. LOL Can I use the 3/8 or 1/4 plywood to tighten the trusses and roof connection?

This is a great forum and I expect to learn a lot here.

Thanks in advance,
Steve

Hi Steve snd welcome to the forum,

I don't believe that reinforcing the trusses is covered in the repair manual. I could be wrong though. I gave my copy of the manual to another forum member a couple of years ago. Maybe someone with the manual could answer that question for us.

I have used 3/8" cdx plywood to reinforce trusses many times. I have never tried 1/4" ply, but I would think the good stuff (not luan) would work. Maybe luan would work also, but the price, weight and strength difference between luan and 3/8" cdx makes the 3/8" a good choice to me. When reinforcing your trusses, you need to be sure not to block air flow. So a total skin sistered on the truss is not advised.

A slight depression, that is strong and secure, is not a real big deal unless it causes water to pond. There is an actual roofing definition for the term ponding. I think it is standing water over 1/4" deep lasting for more than 72 hours. I think there is a square inch stipulation too. This is probably not completely accurate, but you get the idea. My goal is always, no standing water.

JD

Hi JD,

Thanks for the reply.

The 3/8 or 1/4 I mentioned was to be cut in strips approx 2 inches wide and stuck between the top of the truss and the actual roof filling the gap, or raising the metal in this case. Kind of like a shim. I just thought 1/4 would be more flexible.

Thanks again for the answer.

Steve

Shimming the metal up should work as long as the trusses are strong and do not deflect with weight on them. When I reinforce trusses for strength, I move the trusses top and bottom cord to where they should be and sister plywood to the sides of the truss to make them strong. When I am done with the trusses, I can actually do pull ups on the bottom cords. with just a slight deflection.

JD

Thanks JD. I'll give it a try.

I was planning on using 3/8 plywood instead of sheet rock for the ceiling. after the trusses are repaired.

I saw in another of your posts about weight of the panels. I was thinking 3/8 plywood in place of sheet rock would help to strengthen the entire ceiling and are most moisture resistant, just in case. Will 3/8 plywood be OK to use as ceiling panels?

Steve

<edit> I checked and the weight of 3/8 osb is 1.24 # sq ft and 3/8 sheetrock is 1.4# sq ft. 3/8 plywood should be fine.</edit>

If you can swing it, Okalux ceiling panels are available in some areas. Here is a link to the manufacturer. You can ask them if there is a supplier near you.

http://www.okaply.com/moduluxpanels.php

These panels are expensive, but they come prefinished with texture and don't require paint (except for touch-up where you oops) They are also the right weight for your mobile home.

I would think plywood would be light enough. It is lighter than sheetrock I think. Probably less than a pound per foot. The Okaply product, now called Modulux, is a lot lighter, but it is also very expensive. When ordered with the 16o.c. splines, I think they are about $80 a panel. Okaply does make a plain ceiling panel without provisions for strips for about $50 each (12'x4'), which would be cheap considering the finish cost and labor of raw plywood or sheetrock. My supplier does not carry them, so I have only been able to use them once. This was a home that already had a factory ceiling with rosettes holding up the panels and no splines (plastic strips). This was before my local supplier carried the panels, so I was able to order the plain panels. That (not so local) supplier has quit carrying the plain panels and now only has the ones with the strips.

JD