When James Hardie siding products butt into wood-based materials, a 1/8" gap will allow for expansion and contraction of the wood-based product. Caulks and Sealants: James Hardie recommends the use of caulks and sealants that remain permanently flexible.

Do you caulk seams on Hardie board?

Joint-flashing material must be durable, waterproof material that does not react with cement based products. ... Other products may also be suitable. James Hardie DOES NOT recommend using caulk or “H”-jointers for the butt joints of HardiePlank® siding with ColorPlus® technology.

Should fiber cement siding be caulked?

Many professionals, like those at James Hardie, also agree that you should not use caulk on fiber cement siding unless there is no metal flashing underneath. Flashing acts as a waterproofing layer for this type of siding, and caulking will prevent the flashing from doing its job.

Does caulking Hardie board void the warranty?

These such areas are called “field butt joints.” In the case of James Hardie's Color Plus siding, which has a pro-rated 15-year warranty, using caulk at field butt joints will flat out void your warranty!

Do you caulk between siding boards?

Bottom of siding boards should not be caulked

While paint does tend to somewhat glue these pieces together, caulking them is never advised and can cause permanent damage. Also, avoid caulking tongue-and-groove siding boards together.

How To Caulk James Hardie Products

27 related questions found

What kind of caulk do you use on hardiplank?

For regular Hardiplank lap siding (the kind you paint AFTER installation), caulking at butt joints is optional. This from installation instructions: A high quality, paintable caulk is recommended. For best results use caulks that comply with either ASTM C 834 or ASTM C 920.

Should you caulk between soffit and siding?

Similarly, you should avoid caulking the bottom edges and joints of your fascia trim and soffits. Any water that doesn't get into the gutters can be trapped in these areas if they're sealed off.

What do you use to fill nail holes in hardiplank?

ColorPlus® Products

1. ColorPlus® Touch-up Kits can be used to cover nicks, scrapes and nail holes that may occur over time.
2. If the touch up area is larger than the size of a dime, the use of ColorPlus® Touch-up Kit is NOT recommended. It is advised to replace the damage siding with a new section of ColorPlus® siding.

What is the most flexible caulk?

Synthetic rubber is a relatively new caulk category. It is perhaps the most flexible product on the market. Synthetic rubber cures clear and is ideal for exterior joints that typically expand and contract. It can be applied in adverse weather conditions (wet and cold) and stretches and recovers easily without breaking.

How do you fill holes in Hardie board?

1. Sand over the damaged area lightly but thoroughly with a medium-grit sandpaper to smooth any jagged edges and create an easy grip surface for the patch product.
2. Apply the patch product to the damaged area with the flexible putty knife to fill in any indentations or holes.

How do you seal fiber cement siding?

Cut ends of fiber cement siding should have been sealed using 100% acrylic latex primer or paint (Certainteed) or in some cases using an approved caulk wiped on the cut surface (see our notes on Hardieplank installation). And caulk is required at certain joints such as vertical trim at windows, doors, corners.

What is joint flashing?

Bearskin Joint Flashing is a plastic sheet for use as a joint flashing behind every butt joint in the siding. The product is a proprietary plastic, 20-year UV-rated sheet 4 ml thick that is basically a six by twelve post-it note. The easy to use joint flashing sheet that will change the way siding is installed.

How often does Hardie board need painting?

Hardie Plank is also called fiber cement siding. While it's far heavier than aluminum, vinyl or wood, it is extremely durable and typically only needs a new paint every ten to twenty years for maintenance. It is one of the best materials and long-term solutions for protecting your home.

Where do you nail hardiplank?

James Hardie prefers and recommends installation of HardiePlank® lap siding by the blind nailing technique, such that fasteners are hidden by the course above. Fasteners shall be installed between 1 in. and 3/4 in. from the top edge and no closer than 3/8 in.

Can you screw into Hardie board siding?

James Hardie Building Products recommends keeping nails or screws at least 3/8 inch from the end of a plank. ... Drill pilot holes, at each mark, one-quarter to one-half inch deep, to make it easier to insert screws and prevent cracking the siding. Align the bracket holes with the pilot holes in the siding.

What is the best caulk for exterior siding?

Exterior silicone caulk is the most commonly used type of exterior caulk because of its incredible durability and water resistance. Silicone is also a very flexible material, even after it has cured, making it an ideal option for sealing drafty windows and doors.

Where should caulk be applied?

Caulk is applied in areas where the joint is not perfectly sealed and to reduce air or water transition and it is the recommended method to fill cracks or joints up to 1/2 inch wide. Caulk can also be used on wider joints but must be accompanied by other elastomeric products to fill in the joint.

Should I caulk between gutter and fascia?

You can always apply a bead of paintable caulk between the backside of the gutter and fascia to fill the void with additional screws to minimize the fap.

What is the best caulking to use on concrete?

These include polymer, silicone polymer, paintable silicone, and butyl rubber caulks. This type of caulk should be used where concrete slabs meet or where they meet with a building. A polyurethane caulk works best here, but silicone will also do.