Masonite Siding

The outside of our home is masonite. With the water intrusion in the walls it has warped really bad. I found yesterday that under the masonite is fiber board and behind that is sheetrock, both have taken on a lot of water for years and it is literally falling out from behind the masonite.

Is it standard to put sheetrock behind the fiber board?

 

What you have is not really sheetrock, as such, but Gypsum sheathing. It's "waterproof" and fire rated. It doesn't do well if subjected to a lot of water, over the long term, however. I wouldn't say that it is standard, but it's one of the products that was used for sheathing especially in the 50's - 70's and is still in use in some areas today. The biggest reason to use it is for its fire rating.

What isn't standard is to have another layer of sheathing (your brown board or asphalt impregnated sheathing) over the top of existing sheathing. It's likely that the brown board was added later- perhaps the last time the house was sided. Maybe they did it because the gypsum sheathing was in bad shape in some areas or because they felt it would help with insulation (1.3 r-value doesn't help much but it's twice what 1/2" plywood would be at r-0.6) or as an additional air barrier to cover up the seams in the gypsum.

 

So if we are going to remove the masonite to have vinyl siding installed, we need to remove the fiber board and probably replace the gypsum board as well then since it is literally falling out of the walls onto the ground. If you go in the attic you can see it's damaged from water and from the shifting of the home which is an issue we are working on.

We are having the home supported underneath with 20+ piers added which we know the jacking process is just going to mess up more in the home. My question is wouldn't it be better to fix the shift problem first by adding the proper supports underneath THEN work on removing the masonite, fiber board and gypsum? I just see epic fail spending that money then jacking up the home.

We've already had the walk in attics supported to stop the shift up there before they installed the new roof this past week.

 

It is best to address the structural and foundation issues first! It's always best to have a level, square surface to work with.

 

My thinking exactly! My kitchen is off 3/4 of an inch now in areas and every room is different as to how it moves. Thanks for all the help!! I think my home should have been used in The Money Pit movie.