Cement Board Siding Seams

Hardieplank the classic flagship james hardie product is a simple 5 16 inch thick by 12 foot long lap siding in widths ranging from 5 1 4 inch to 8 1 4 inch.

Cement board siding seams. James hardie believes it is good building practice to seal the joints to prevent moisture such as wind driven rain and snow from penetrating the wall cavity. Weatherside fiber cement siding is the 1 and weatherside fiber cement siding is the 1 and only solution for replacing or repairing old asbestos siding shingles. For pricing and availability. Manufacturers caulk and sealant recommendation sheet s 100b issued july 2000 application.

James hardie 8 25 in x 144 in hz10 hardieplank cedarmill fiber cement lap siding. We only caulk butt joints on cedar siding if previously caulked. It does nothing else but produce fiber cement siding and cement backer boards. A common problem with cement board siding products and some other types of horizontal lap siding is that older installation guidelines called for caulking the joint instead of flashing the joint.

Buckled fiber cement siding is most likely to occur because the installer failed to give the recommended gap between the ends of the fiber cement boards and abutting vertical trim at corners windows doors etc. Our siding close up photo at page top illustrates what may be another clue in the history of a failed installation. Fiber cement siding accessories. We can see a hard dried layer of caulk that was a bit under 1 8 inch wide inside of the now wide open butt joint between two siding boards.

For pricing and availability. Pretty much all trim joints need to be sealed. Traditionally board and batten siding starts with wide vertical planks boards which are then joined together by thin vertical strips battens to cover the seams. Trim boards wood windows.

This has proven problematic over time as caulking the joint results in unsightly surface appearances due to the different textures as well as resulted in failure of the caulk joint and associated ongoing maintenance. It s available in a variety of sizes and shapes to match many of the old siding shingles installed over the last 60 years. In this video i show you how to tape cement board joints. It is a very simple process and i used some fibatape and thinset mortar to seal the cement board j.

Fiber cement boards are caulked only when there is no metal flashing behind them.