Need advice on drywall backing

[beetz12]

Hi everyone, this is my first post. My wife and I just recently acquired our first investment property. The house was built in the 1940s and has been neglected for most of that time. It is a single family house that's been converted to a duplex and some of the modifications done are quite questionable.

The first thing we noticed is that the laundry room floors and walls are a bit out of whack. I removed the old subfloor successfully but the drywall is another story. After removing the back section, I found what looks to be the wooden siding of the house.

In this case, should I repair the siding using similar materials and then put the drywall back, or should I take out the "siding" completely, or should I do something else all together?

Also, there's insulation in the walls that seems to be falling apart. Can I leave them as they are or should I remove them and / or replace with something else?

Thanks in advance!

 

[Snoonyb]

Welcome.
What you think is siding, could be, if it's greater than 3/8" thick, and if it's not, just wide wood lathe.

The ins. is old rock-wool and can be replaced with R-13 batts.

 

[beetz12]

Thanks for the reply Snoonyb. You're right, they are wood lathes.

Should I replace the broken / missing pieces before I put the drywall back?

 

[zannej]

Are those interior or exterior walls? If they are exterior, is there insulation behind the wood lathe?
If you anchor the drywall to the studs, you probably don't need to replace any of the broken pieces of wood lathe, but it is up to you. My friend drywalled over the wood lathe that was damaged in his house and had no problems. I don't think replacing broken pieces is necessary since the studs should offer enough support for the drywall to stay up. But, that is just my opinion.
If you don't have insulation in exterior walls, now would be a good time to add it.
Also, do you plan on adding more electrical outlets? Holes in wood lathe might be a good spot to put things. It will be harder to cut through existing wood lathe once drywall is up. Not by much, but it will still take added effort.
I've found that houses from that time don't have enough electrical outlets to meet code and are not convenient for plugging things in.

 

[Snoonyb]

Thanks for the reply Snoonyb. You're right, they are wood lathes.

Should I replace the broken / missing pieces before I put the drywall back?

I would make sure any loose was securely nailed and fill in sections so that there is a relatively even plain, for the DW, and as zannej implies, there is a learning curve, when adding or upgrading utilities in older structures.

 

[Sparky617]

It doesn't look like lath to me, it looks more like tongue and groove "bead board" Was this laundry an addition and could this have been an exterior wall? To my eye I'd think this was sheathing given the age of your house before the widespread use of plywood in residential construction.

As to removing it not needed. You don't even need to fill in the blank spots as long as the gaps aren't huge. Drywall is typically unsupported between studs, so as long as your holes aren't big you can just drywall over them. Main thing is to have a level/plumb backing to attach your drywall to and don't screw into the areas without the bead board.

 

[zannej]

Sparky, my friend's house has the wood slats on interior walls as well as exterior, so I think having them was a very common thing at some point. I believe his house was built around 100 years ago. His house doesn't even really have studs-- just the horizontal boards (but they are much thicker). His old house that burned had studs and the wooden slats and he drywalled over it. Like the OP's house, he had some broken pieces of wood that he removed. He did not fill in voids, just drywalled over.

I will say that he found putting drywall up horizontally so the longways spanned over studs seemed to work well for the stability of the walls.

Having the slats behind drywall will add some extra stability and maybe even noise reduction so its not bad to leave them unless you wanted to preserve them and use them for something else by carefully removing them. But, I'd recommend leaving them and covering over. Maybe leaving a newspaper or note in a plastic bag or something inside for the next person who goes pulling down walls.

 

[Sparky617]

Sparky, my friend's house has the wood slats on interior walls as well as exterior, so I think having them was a very common thing at some point. I believe his house was built around 100 years ago. His house doesn't even really have studs-- just the horizontal boards (but they are much thicker). His old house that burned had studs and the wooden slats and he drywalled over it. Like the OP's house, he had some broken pieces of wood that he removed. He did not fill in voids, just drywalled over.

I will say that he found putting drywall up horizontally so the longways spanned over studs seemed to work well for the stability of the walls.

Having the slats behind drywall will add some extra stability and maybe even noise reduction so its not bad to leave them unless you wanted to preserve them and use them for something else by carefully removing them. But, I'd recommend leaving them and covering over. Maybe leaving a newspaper or note in a plastic bag or something inside for the next person who goes pulling down walls.

By the 1940's plasterboard lath was becoming pretty common. It is kind of a forerunner to drywall but the pieces were smaller and it was meant to be coated with plaster. It was pretty uncommon to sheath both the interior and exterior side of a wall. It happened but wasn't very common. I was doing some volunteer work for Appalachian Service Project in Rainelle WV a few years ago. The town had been flooded and many homes were damaged or destroyed. ASP did repairs and new builds. Any way, this town used to have a huge saw mill that processed wood from the surrounding mountains. Including a lot of American Chestnut from back in its heyday as one America's great hardwoods used for furniture and flooring. So this one house my team is repairing had tongue and grooved chestnut as sheathing on the interior and exterior sides of the walls. Most of it was stuff that wasn't a high enough grade for flooring and it was readily available in this town. Other than that one house, I've not seen people sheath both sides of a exterior wall or any side of a interior wall.

This video has been around the interwebs a few times.. the guy is installing plasterboard lath, not drywall.

 

[mabloodhound]

Those boards are just fine BUT you should really try to insulate behind them and in the next bay(s) also. Then just replace with new sheetrock/drywall.

 

[zannej]

By the 1940's plasterboard lath was becoming pretty common. It is kind of a forerunner to drywall but the pieces were smaller and it was meant to be coated with plaster. It was pretty uncommon to sheath both the interior and exterior side of a wall. It happened but wasn't very common. I was doing some volunteer work for Appalachian Service Project in Rainelle WV a few years ago. The town had been flooded and many homes were damaged or destroyed. ASP did repairs and new builds. Any way, this town used to have a huge saw mill that processed wood from the surrounding mountains. Including a lot of American Chestnut from back in its heyday as one America's great hardwoods used for furniture and flooring. So this one house my team is repairing had tongue and grooved chestnut as sheathing on the interior and exterior sides of the walls. Most of it was stuff that wasn't a high enough grade for flooring and it was readily available in this town. Other than that one house, I've not seen people sheath both sides of a exterior wall or any side of a interior wall.

This video has been around the interwebs a few times.. the guy is installing plasterboard lath, not drywall.

There was no plaster in my friend's walls but they put up wood paneling over the slats. That video is very cool.

I agree with manbloodhound on the insulation.

 

[Snoonyb]

By the 1940's plasterboard lath was becoming pretty common. It is kind of a forerunner to drywall but the pieces were smaller and it was meant to be coated with plaster. It was pretty uncommon to sheath both the interior and exterior side of a wall. It happened but wasn't very common. I was doing some volunteer work for Appalachian Service Project in Rainelle WV a few years ago. The town had been flooded and many homes were damaged or destroyed. ASP did repairs and new builds. Any way, this town used to have a huge saw mill that processed wood from the surrounding mountains. Including a lot of American Chestnut from back in its heyday as one America's great hardwoods used for furniture and flooring. So this one house my team is repairing had tongue and grooved chestnut as sheathing on the interior and exterior sides of the walls. Most of it was stuff that wasn't a high enough grade for flooring and it was readily available in this town. Other than that one house, I've not seen people sheath both sides of a exterior wall or any side of a interior wall.

This video has been around the interwebs a few times.. the guy is installing plasterboard lath, not drywall.

The original version of "rock lathe" was called "button board", because in had preformed holes which were there to insure the plasters adhesion, and as gypsolite products matured in formulation, rock lathe, without holes, became the resulting lathe product, shown in the video.

 

[Sparky617]

The original version of "rock lathe" was called "button board", because in had preformed holes which were there to insure the plasters adhesion, and as gypsolite products matured in formulation, rock lathe, without holes, became the resulting lathe product, shown in the video.

In the video you can see some of the boards with holes. Even the screen capture on my post shows in some of the boards, not what he's installing in the video though.

 

[Snoonyb]

Typical photos of button board;

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