How to Replace a Rotting Post

Keep that porch or patio roof over your head with this repair project.

Don't let the rot spread further-give your roof the support it needs with these step-by-step instructions.

Materials and Tools:

column jack
power drill
nut driver
scrap lumber
circular saw
levels
pry bar
wrench
hammer
folding rule
carpenter's square
hacksaw
rasp
glove
safety glasses
dust mask
pressure-treated 4-by-4-inch support post, cut to length
upper and lower brackets
galvanized nails
washers and lag screws

Steps:

1. Drill out rivets to remove the existing downspout.

2. Set up a column jack next to the existing post. Place scraps of wood at the base and top of the jack. Before lifting, use a magnetic level to make sure the jack is perpendicular or plumb.

3. Use an adjustable wrench to raise the roof until it's level.

4. Pry the existing post away from the roof and cut through the nails with a hacksaw.

5. If the original base plate is set in concrete, use an elevated base plate to avoid digging out and re-pouring the concrete. The new plate fits inside the original and raises the base of your new post off the ground without tearing up your patio.

6. Use a folding rule to measure the distance between the new base plate and the roof.

7. Wearing eye protection and a dust mask, cut a new 4-by-4 post with a circular saw.

8. Smooth the cut edge of your new post with a rasp.

9. Attach new base plate to the bottom of the post, and attach the top bracket to the top. Slide the post into position, and use a hammer and a scrap piece of wood to knock the bottom of the post into the old bracket.

10. Secure the post at the top by driving in galvanized nails.

11. Drill pilot holes at the base and use lag screws and a washer to connect the post to the existing base plate.

12. Replace the downspout and drain system.

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