How to Remove and Replace a Rotten Subfloor

I'm b cody and i'm ashley, whether you're remodeling your entire home or just sprucing up one room with a fresh coat of paint, we'll show you how to do it right. This house is in very good condition, but there is one project we have to tackle before we move on to anything else. Look at this floor, it's terrible and we need to

replace

it, but it's not as scary as it looks. I promise there are two common ways to build a house. The first is called slab. At ground level a wooden form is built, all sewer and water lines are placed inside the form, reinforcing wire is added and then the form is filled with concrete.

The second method is to build a house with a basement or cellar. It has a crawl space and sits about two feet off the ground on concrete blocks, the floor joists rest on the blocks and then plywood is added to the top of the joist to create the

subfloor

. Some flooring can come in various materials, you have osb particle board. untreated plywood board or untreated tongue and groove plywood before we repair anything we need to find out why this floor rotted in the first place, the

subfloor

rots due to moisture, but where did the moisture come from, maybe there is a leak or something that was fixed in the past that we don't know if this damage was caused by a leaking water pipe, we would probably find more rot near the kitchen sink or dishwasher.

The floor is not rotted under the window, so we can rule out a leaky window and the attic. The spaces look dry, there are no signs of

rotten

wood up there. I'm pretty sure the moisture comes from the ground. The lot this house is on is a little low, so I'm thinking it holds up a little under the house. humidity all the time yes, the summers here in Florida are very hot so I bet the moisture is evaporating on the subfloor. I totally agree, but good news is that the 2x8 floor joists are in excellent condition.

I didn't see any signs of wood rot. when I was crawling around down there, that's great, but how are we going to minimize the amount of moisture in the crawl space? To start, we can install a fan in the crawl space to increase airflow and reduce the humidity there right now, water runs off. the roof to the ground directly next to the foundation by adding gutters and downspouts we can divert water away from the house we can also install a vapor barrier under the house it is a plastic sheet that prevents moisture from accumulating under the subfloor and the floor joists, all of these little fixes will really help us with our moisture problem, but now it's time to start working on the rotted floor.

There are two ways to repair this floor. We could cover the existing hole with plywood, but getting the new subfloor to match the old subfloor perfectly is not something we want to tackle, so what we're going to do is take out these cabinets and do a full demo of these kitchen floors, which which means we're going to start from scratch, but that's great, it will ensure that our floors are completely level. There are many tools we could use to cut this subfloor. In this case, we will use a circular saw before we begin any demonstration, be sure to use it. your safety team we have identified where the electrical and plumbing lines will be, but to be safe we ​​are going to take things slow, we are going to trim the subfloor one section at a time, use the pry bar to

remove

the subfloor and pull out the nails Let us find and inspect the next section of plumbing and electrical.

I started the demonstration by removing the rotted plywood. This thing was so brittle that all I had to do was let the weight of my mallet do the work on this part. The tedious part was removing all the nails from the floor joists. I don't know of a quick way to do this, you just have to pull out the nails. one by one, the last thing we want to do is cut the floor joists, so what we're going to do is measure the thickness of the subfloor and adjust the depth of our blade to match. Be sure to keep your hands out of the way.

The blade while adjusting the depth cuts the floor into small squares makes it much easier to break them up and take them to the trash, but this process still took a long time, some parts of the floor actually had two layers of plywood to cut. I went through and up and took it easy because cutting my leg on a rusty nail or having an accident with the circular saw wouldn't make Ashley very happy. After cutting the entire subfloor, I used a reciprocating saw to clean up the edges. of the floor near the walls and to get rid of the rotted subfloor under the hardwood, I

remove

d several pieces to expose the rotted wood and then set the depth of the circular saw blade to match the depth of the hardwoods and the subfloor to be able to I didn't cut the floor joist, so I used the existing edge of the hardwood as a guide to clean up the edge after a little more demo of the

rotten

wood, we are ready for the next step now that we have a big hole in floor. need to cover, we will start by measuring the area to determine how much plywood we will need.

You can measure with a standard tape measure or use a laser tool like this one. It looks like we have about 250 square feet to cover the plywood. It comes in four foot by eight foot sheets, so I think eight pieces should work, but we can't just lay down plywood. We want to attach each side of the plywood to the substructure of the house. We need to add boards between the floor. joists to screw the new subfloor on, we will use two-by-six pressure treated lumber like this one. We also want to make sure all the floor joists are level, if they are not level we will shim pieces of wood or add boards to level the floor joists it looks like the floors are level so it is finally time to put down the subfloor to prevent them from The floor squeaks when you walk on it.

We'll add a drop of glue to each joist so the plywood subfloor doesn't separate later. I like to use two-inch deck screws on projects like this with a cordless impact driver. It is important to leave a space of 1.8 inches between each sheet to allow the wood to expand naturally during the seasons in which we begin laying. We brought down as many full size sheets of plywood as we could. It felt great to cover almost half the floor without cutting a single piece of plywood. Well, we can't fit any more sheets of plywood in this space, so here we are.

We will have to start cutting pieces to fit the spaces. It's like a giant puzzle, piece by piece. We applied the measurements from the floor to the uncut plywood, drew lines with a box of chalk, and used a circular saw to make the cuts after adding more. We glued it to the floor joists, put up the plywood and screwed it all together, look, that wasn't that scary, but it was a huge project and that's something to consider when doing home renovations like this and there's no shame in hiring a professional to do the job, but if DIY is what you do, now you know how to do it right.

Hello guys, thank you very much for watching this video. Be sure to hit the like button and let us know in the comments if you want to do this. Try any of the tools we use in this video. We leave links in the description below, as well as some links to additional articles to help you with other flooring projects. If you would like to see more of our instructional videos, please subscribe. button and stay tuned to the lowe's youtube channel