Redoing Floor On Front Porch‏

Question: I want to start the project of redoing the front porch floor, it was built in 1900, that is old and some boards are broken. Any Advice?

Answer: You should remove all the end floorboards and check the floor joists for rot, before replacing the floor. You may have a problem patching as the slats currently in place are probably thicker than new lumber, you may have to use a shim board on the joists to raise the slats so that they are all at the same level. Use stainless steel, galvanized screws or nails if you are using regular lumber. If using pressure treated lumber you need to use copper coated or stainless steel fasteners. Paint the underside and edges of the slats before installing to protect them from the elements.

Ceiling Joists Bearing Weight‏‏

Question: I am planning on installing drywall to my garage ceiling, to give it a more finished look. I am concerned about the load on the joists since there are only 2x4's from one side of the garage to the other 20' total length, supported in the center by another 2x4 attached to the gable. Additionally the joists are spaced every 32". I suppose the 2x4 are there only for lateral support and not meant to support a load. Other houses in my neighborhood have installed drywall after initial construction, and were built is the same way as my garage.

I am planning on installing more 2x4's to make it 16" on center, and install 4 pieces of 4x8 1/4" plywood on top of the rafter for light storage and than install thin drywall 3/8" I think. Also the garage dimensions are 20x20.

That's the scenario, my question is, is there a formula that I can use to find out how much of a load these 2x4 joists can support safely?

Would adding additional 2x4's to the existing 2x4 joist's work? Make it two or three 2x4's wide.

Also I can't seem to find good Douglas Fir 2x4 that are 20' in length, if I added a 16' length and a 8' length for a total of 20' would that still add support even though it isn't one solid board?

Answer: Adding a second 2 x 4 that does not extend the full length does little if anything to add load ability.

What I would suggest is add a double 2 x 4 sandwiching a piece of 1/2" plywood, joint staggered as the joist in between to make your 16" centers.

Use construction adhesive and nails when making the sandwich. 3.5" nails driven in on an angle, a 5 pattern (dots on a dice), construction adhesive on both sides of the plywood.

Construction

Redoing Floor On Front Porch‏

Ceiling Joists Bearing Weight‏‏

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