DIY Guest House Renovation – Drywall

diy drywall installation modern atomic family

Through a limited experience with diy drywall on a Habitat for Humanity project, I knew that drywall was an awkward and messy project. Originally, I only wanted to remove the old drywall on the garage-side of the shared wall that split the garage from the guest house. This was to help the professional electricians run new electric lines, as well as to add insulation. But as I’ve learned, it quickly grew from a “simple” job, to basically stripping 90% of the drywall from the guest house.

drywall removal before after diy

Removing the old drywall from the garage side of the shared wall.

I read that some old drywall boards could contain asbestos, so before I started the project, I called my local environmental abatement company (I designed a website for them) and had them come out to test. They weren’t worried as much about the drywall as much as the TAPE used between the boards. But thankfully, no asbestos was found, and I proceeded to the fun job of tearing everything out on the garage side of the wall.

termite damaged sill plate

The sill plate of the shared wall was so termite damaged that it just disintegrated.

Then I hit snag-project-extender #1. The sill plate of the divider was absolutely riddled with termite damage and basically a shell. It disintegrated with minimal effort. I couldn’t very well put drywall back on this wall with a rotten sill, so the guest-house side drywall came off so I could replace it. Not only was the sill rotten, but it was never even secured to the garage floor. I was lucky that the termite damage was mostly constrained to the floor, and I only had to replace one damaged stud.

wall supported to replace sill plate

Supporting the wall while replacing sill (left) and completed sill plate with one termite-damaged stud replaced.

Because this was a load-bearing wall, I was very careful about supporting the structure as I removed the sill, and replaced it in sections, using pressure treated lumber. I also made sure to secure the new sill to the garage floor by drilling holes in the concrete, filling with adhesive, and using wedge anchors. I also used this as an opportunity to remove the old doorframe, as I’d be installing a new pre-hung door. It was also at this time that I had the remodeling company come in and run electric lines.

moldy bathroom drywall

Mold on the original bathroom drywall (left) and the framework for the bathroom vanity and lighting (right).

Then I was lucky to find MOLD in the old drywall along the kitchen/bathroom wall. Obviously, there had been a broken pipe in the past, as the all the old remaining drywall was moldy and crumbling about 5” up from the floor. In addition, I didn’t like how the electricians installed the bathroom fixture AND I needed to build an enclosure for the future inset bathroom vanity cabinet. So… off came most of the bathroom drywall, too! (Can you say snowball?).

diy drywall without mud

The new drywall is hung! View to the kitchenette and bathroom (left) and toward the garage (right) now with new door. The open area will be covered by the kitchen cabinet. I left it open so I could easily access the electric and plumbing for the future kitchen sink and small water heater, which will be placed IN the cabinet.

With all the damaged drywall removed, bathroom light electric repositioned, and termite-damaged sill fixed, I could finally install the new drywall! The original drywall in the bathroom was not greenboard (used for damp areas) and I should have done the right thing and stripped it all and replaced with proper drywall made for damp areas, but I didn’t. I figured the bathroom would only be occasionally used, and I installed a high-powered vent-fan. I might regret it in the future, but for now, its fine.

We removed the kitchen cabinets and set them aside for a minor restoration as well as removed the horrible thinset floor (blogs coming soon!) I also installed a new pre-hung door we purchased from Home Depot. Technically, this door should be fire-rated but they were unbelievably expensive. So after all this, I finally I got to hang the new sheets of drywall. I won’t go into too much detail as cutting and hanging drywall is a pretty straight-forward process. Because we wanted to keep the open-beams, we didn’t need to install drywall on the ceiling, which is a bit more complicated.

A few amateur tips: Make sure to measure electrical outlet holes VERY carefully and cut using a specific drywall saw. Don’t embed the drywall screws too deeply, but they shouldn’t stick out, either. Use 3/8″ spacers to keep the drywall off the floor! You don’t want to set the drywall right on the flooring as it will wick moisture up and cause mold/mildew issues.

diy drywall mudding

Mudding and sanding/feathering complete. Not as widely feathered as the pros, but it’s good enough.

Mudding the drywall was pretty straight-forward as well, though taping was tricky. After getting used to it, I personally liked the “pro” paper tape rather than the “mesh” type as it was much thinner and easier to work with. There are hundreds of mudding “how-tos” so I won’t go into it here. Obviously you’ll want to cover all screws, which should have just barely been indented into the drywall. For the joints, you want to mud the tape, feather the edge and then begin layering. Let each layer dry completely, and sand it between layers, which could take some time depending on the thickness of the mud and how humid your area is. Each successive layer is designed to hide the joints/tape and should spread wider and wider to give the illusion of a perfectly straight wall. Last thing you want is a chunky lump of mud at each joint. I didn’t feather it out nearly as wide as the pros do it, but it was just fine for our little guest house.

Open windows, wear old clothes, and absolutely wear some sort of appropriate respirator or mask when sanding! The quantity of fine, drywall dust is amazing and it gets everywhere, not to mention the health issues for those exposed. So be safe, and protect your lungs. Some folks even hold the shop-vac (with a proper filter installed) as they sand but I found it clunky and awkward.

diy drywall primer

New drywall complete, including a couple coats of drywall primer.

Once I was satisfied with the drywall, we decided to paint it with a type of drywall primer. I’ve read it’s not THAT necessary, but we went ahead and did it. Turned out great! Only I can see where my mudding wasn’t quite perfect. We then installed ½” quarter-round trim along the roof edge to cover the rough edge there, and once we installed the flooring, we added appropriate baseboard trim.

Once the electric was run and drywall up, I installed insulation on the garage side of the wall, which has greatly helped keep the temperature down. With the open beam ceiling (and no roof insulation) the guest house can still get quite warm, but nothing that the small window A/C unit (or a small space heater for the winter) can’t handle. Eventually, I will install fire-rated drywall on the garage side, and maybe save up for a fire-rated door, but that is after I run electric for the garage.

Up next, Flooring!


  • I’m so impressed with the drywall you installed! I’ve got a large room that I’d like to separate with a partial wall, and I’ve been worried about doing it properly and getting the trim right. This gave me hope, so thank you for sharing your experience 🙂

    • Patricia Winter-Hunt

      Thanks! We were a bit intimidated working on such a large area, but it came out nicely in the end. Good luck on your install!

    • Thanks for the kind words, Stephie. It takes a bit of practice and patience but it can be done by any dedicated DIY’er. Good luck!

Leave a Reply

Your email address will not be published. Required fields are marked *

11 − 1 =