Adding Ceiling Joists In The Attic

They must span at least three joists for stability.

Adding ceiling joists in the attic.

Standard joist spacing for the installation of attic flooring materials is 16 inches on center oc meaning the distance from the center of one joist to the center of the next joist is 16 inches. Illuminate dark corners of the attic using portable battery operated lanterns or clip on workshop lights. Assuming that the wood ceiling attic floor joists are sound i was thinking that instead of removing all the existing plaster a messy job while people are living in the house we could install new 5 8 thick drywall to form a new ceiling and thereby confine the old plaster. That s a big size and strength difference between the two types of attic joists even if the joist spacing is the same.

If the attic were designed as living space those ceiling joists would become floor joists and be much bigger. Use of joists in attic flooring covering the ceiling joists in the attic using plywood is a cheap way to make better use of the wasted space in your house. If the attic joists are not adequate one way to strengthen the floor for live loads is to sister the old joists. Sistering is the process of adding a new joist next to each existing joist.

In the case of 2x6 joists you can pair them up with additional 2x6 joists by nailing them together side by side. Sistering installing new larger joists next to the existing ones is one way to bring your attic floor up to code. Often existing joist bays are filled with electrical and heating ducts that will need to be relocated. The subfloor installation is easy.

Gluing and screwing a 3 4 attic subfloor and providing solid bridging should also be considered. Precise measurement is the most difficult as you need to consider all underlying obstructions carefully before proceeding with your plans. If you lose your balance you could crash through the ceiling. Ceiling joists are typically 2 8 lumber floor joists are usually 2 10 or 2x 12 lumber.

I m wondering if i could slip the needed support beam above the ceiling and hang the joists below the beam to keep the ceiling free of intrusions. The bedrooms are both on the back wall of the house at the gable end so a small hole would allow a beam to slide into the attic. Use a piece of plywood or a couple of sturdy wide boards as a standing surface and move them around as you work.