How Many Posts To Support A Roof

Any post that will touch the ground should be pressure treated for decay resistance.

How many posts to support a roof.

Patio roof posts columns. According to the old af pa table a 4 foot douglas fir 4x4 post can support 256 square feet of deck. In other words the maximum distance it can cover without support from posts. Measure the distance between the bottom of the porch roof and the top of the ledger beams of the porch.

Consult with a structural engineer local building officials and contractors who specialize in this work. Step 2 post height. While many like to use the smaller 4 x 4 posts they can tend to warp after they have been standing under the weight for several seasons. Most deck roofs require separate footings from the deck to support the weight of the roof throughout the seasons.

We just completed a beer garden addition with a single sloped roof. If the deck doubles as a porch it needs to be able to support no more than 80 psf. For deck roof posts dig holes for the roof posts and pour cement to keep them secure. Solid lumber such as 4 by 4s 6 by 6s and 8 by 8s.

The international residential code requires railings on any deck that is more than 30 inches off the ground. Load bearing posts must have a solid footing on undisturbed soil and all parts of the post must be fastened together. Sometimes they e built up from more than one size of lumber. Posts and columns may be made from several types of materials.

In all probability for this size deck you need to be talking 3 rows of support beams with 3 4 posts each one beam near house one near outside edge one down the middle to be able to get to economical and realistic joist spacing 16 or 24 and realistic post size 4x4 or 6x6 and beams 4x12 or smaller. Posts and footings support the weight of your house so you have to size them right. Using the 2005 nds i calculated that the same post can support 231 square feet so it would seem there s no problem using 4x4s to support say an average sized intermediate stair landing. Here we look at the most common.

Porch decks also require larger footings than deck footings. The span on your porch posts is determined by the weight load of the roof. However if the spacing is too wide the patio cover s beams will bow under the weight of the joists and roof covering materials. It was 16 wide x 40 long.

Large 8 x 8 posts are necessary for the use of supporting a porch roof. Our main support posts are 8 on center with a 2 x 10 on the inside and outside of the post at the top and a double 2 x6 top plate. For post material choose one such as pressure treated pine that will resist rotting and insect damage when it is planted in the ground. The length of your posts will help determine the height of your carport roof.

Most builders use 4 by 4 inch lumber.