Patching Cement Board Siding

Repair or patching fiber cement board siding dents chips cracks and other minor surface damage in james hardie siding and trim products can be filled with cementitious patching compound.

Patching cement board siding.

Put on a pair of rubber gloves. Mix a solution of 1 2 cup trisodium phosphate and 1 gallon of water. Using a stiff brush mix the patch material specifically intended for fiber cement following the manufacturer s directions carefully. Use only as much water as the manufacturer recommends.

0 312 in x 8 25 in x 144 in hardieplank primed woodgrain lap fiber cement siding panel. Use only completely acrylic paint and apply with rollers. Apply the patch product and paint on a day with no rain to speed drying and curing time and prevent water damage to your patch project. Depending on the size of your house you may need a ladder to reach the area of siding near the roof.

Patching fiber cement siding. Dip a soft bristle brush into the solution then scrub the cracked area of fiber cement siding to remove dirt and debris. The e cut blade works great for cuting out the nails. Hardieplank is a cement lap siding product used on commercial and residential exteriors and is designed for very low maintenance and a long useful life.

This will allow the patching compound to lock in behind the cement board. The cement basis of the product dictates the use of thin set mortar to properly repair cracks or holes. Rinse the siding with clean water to remove the soapy residue. If you are removing more than one level of siding in an area start at the bottom and work your way up.

Though it is a tough wearing product the surface of the siding can sometimes be damaged during installation by unusual wear or by impact. Make sure that the siding is completely dry from the washing and that the caulk and patches are dry too. These areas include but not limited to penetrations flashings plank and trim connections and in some cases between plank joints. Remove the nails and countersink any nubs that might prevent your new siding from sliding up under the old.

Fein multimaster is excellent for this. For holes larger than 1 2 inch in diameter use a carton knife or carbide tipped tool to cut a v shaped groove behind the edges of hole. Use wood shims to hold the top board away from the wall while you continue to remove nails along the length. Refer to manufacturer recommendations for products that are compatible with fiber cement.

If its blind nailed you can usually stick a couple of wood shims under the next clap to give you a bit of clearance. Fiber cement siding repair or patching re applying caulking when it has begun to show signs of wear can help keep moisture from getting into the wall cavity.