Issue link: https://read.dmtmag.com/i/320565
JUNE 2014 20 THE JOURNAL BY GEORGE PORTER SERVICE & SET-UP I Think There's A Problem Here Did you ever have one of those little thoughts nagging around in the back of your mind while you're doing something that you've probably done a hundred times before. It's the little no- tion that you think there's something wrong here, but you just can't quite put your finger on it. Well, that little thought boiled to the surface the other day when I was reviewing an installa- tion manual for a manufacturer. I was doing the part where they described mating up one half of a double to the other and most of the companies treat this in pretty much the same fashion. They say you block and level one half of the home— the heavy half if you have a choice. At this point, they generally mention something about rolling and jacking equipment. It basically says you get one half over there and then you raise the inside I-beam until the two floors are joined together and there is a gap in the roof. Most manuals then say you then lag-bolt the two halves together loosely, then you raise the out- side I-beam until the floor and the raised half be- comes level with the floor in the half that you had previously set. Now here's the problem—what happens to the house between the outside I-beam and the marriage wall? If the floor remains straight across, then the inside I-beam will have to lift off of the inside blocks. But with all that weight, it can't. So it does one of two things. The home either sags a little to leave the I-beam sitting on the blocks and putting large force on the mar- riage wall, or the lag-bolts will rip out. If you don't think you're inducing some kind of stress into the home by doing this, next time try it just once without putting the lag-bolts in. The floor in the half you're jacking will drop below the floor of the one you have set just a little bit when you raise the outside I-beam. So, if it stays put when you do this, and if you've put enough lag- bolts in it, it should; then the floor joists and decking and frame and outriggers on both halves of the home are put under a considerable strain. If you are not using a water level, to set all the piers first, you'll probably never discover this strain and it will be trying to relieve itself over the life of the home. As these floor joists and decking relax, creaks and separations will occur along the marriage line and in the floor of the home. Drywall may de- velop stress cracks and you'll need to make a couple of more service calls on this house because of "settling." If you set all the piers under all four I-beams with a water level, raise the home, bring it over and set it down on those piers, the home should (but might not) be extremely tight together, the floor should be level, and when you connect those two halves together, there should be very little strain between them and the structure will not be trying to slightly change its shape as time goes on. In a perfect world that is how it should be but in case you haven't noticed...... so here is an idea for you. Here is an old trick you might try sometime. Now, you can only use this on homes that will not be set on a block wall and only two section homes. so basically only homes with skirting or a block wall installed under the perimeter after it is set. When you set up your water level and I suppose a laser level as well, pull a roof shingle out of the pack and cut a cap shingle out of it. You are going to put this under the bottle or machine or whatever you are level- ing it with. Pay close attention to this part! You will place it under the bottle only when you level the outside beams and remove it when you do the inside beams. Take a few extra minutes to be really careful when setting the wedges or jack stands or whatever you are leveling. Be very precise here because it is going to pay off well in the end. What you are doing is ever so slightly tilting each half toward each other and this will make the roof nice and snug. Or at least more snug than it would have been without this ma- neuver. So why do we have to do this? Why don't the factories make them perfect? Well I am sure they try but they are human just like us; so for- get perfect. There are some other factors that can change the shape of a home as well. For in- stance look at the weight distribution on a home as it travels down the road. I don't mean the camber, I mean the sidewalls. One side of a section has doors, windows, cabinets, kitchen appliances, maybe a fireplace, six inch walls with drywall, and the other has big openings covered with plastic. This is not balanced and it really can't be, so it tends to lean to the heavy side a little bit. The other half has the same problem but in the other direction. Put several hundred miles under one of these things and guess what you have got....roof gap. Now if it was straight when it left the factory it should go back together pretty well; especially with our little shingle trick. But...If the roof gap is large and there are no drywall cracks that show that it moved then guess what? They built it that way I think. I am trying to think of a way to move the "bones" of the house without crack- ing the gypsum and I can't come up with any- thing but I would be willing to listen to someone who knows how this can happen. Point is, as installers we need to fix little stuff and make it all happen. But you need to know when a "fix" is possible and when someone needs to get into the reconstruction of a roof system. When you try to move a roof many inches and the framing starts to separate you better stop right there, Better yet don't start, it might be something you can't finish. Try the shingle thing, it really works if you are careful. George Porter is a consultant to the manufactured housing indus- try. His Company is Manufactured Housing Resources, P.O. Box 863, Rehoboth Beach, DE 19971, (302) 645 5552, Web: www.george-porter.com Some of his services are both in person and On-line training for certification in many states plus expert witness and investigation for the industry. T J