Calculate how many pieces of siding it will take to cover a wall or gable with this simple tool. Easy to use radio buttons and number fields.

Siding Calculator

Select the coverage and the length of the boards. These choices are for the most common sized siding available. For a custom application, just select the next largest size.
Select whether its a wall or a gable. While both are really walls, what this selection is about is whether its a rectangle or a triangle.
Select whether or not its tree sawed siding or engineered. The main difference here is that the calculator allows for 10% extra for engineered and 60% extra for tree sawed siding. It takes quite a bit more for the tree sawed because so much of it typically has to be culled. A good example is cyprus. It’s widely used, but installers often don’t allow near enough for the the many boards that will simply not be able to be used. Vinyl, fiber cement, and high end wood products are good examples of when to select the engineered button.
Enter the dimensions for the wall in feet. It’s pretty simple just select the number field and use feet for the length and height. It does not matter if it is a gable or regular wall. The previous field takes care of that.
It is an option to enter the approximate square footage for the openings. Some installer simply do not do this. However, this calculator already allows for extra boards and if you do not do this step you could wind up with a great deal of extra boards.

Board & Batten

While this calculator is specifically designed for horizontal products, it can also be used to estimate board and batten. Just rotate the wall 90º in your mind. For example, if you are using a 1 x 8 product and it covers 7 1/4″ and the wall is 9′ by 20′, then select 7″ for the coverage, 10′ for the length, 20′ for the height, and tree sawed for the type of material. If the battens will be ripped from the parent building material, then this must be added manually. Its pretty simple though, just take into consideration how many battens will be ripped from a single piece of siding and convert that to a percentage. For example if the material is 7 1/4″ wide then three battens 2 3/8″ will be yielded while allowing for the two 1/16″ saw kerfs. In other words, since three boards come out of one, then simply add 33% to the total for each wall. If four boards are yielded, then add 25%.

Chimneys and Cupolas

For horizontal applications pertaining to small walls, always do each wall separately. While it is tempting in certain situations to add the length of some short walls together to save time while doing estimating, it may not work out so well to cut this corner.

Tips for Estimating

Most engineered siding products such as fiber cement boards, smart trim, and even PVC vinyl come in 12′ or 16′ lengths. Most pick-up trucks can haul these products, but they present challenges. If you are using tree sawed material and it is available in shorter lengths, and the hauling capabilities are a concern, then it would only make sense to choose shorter boards. For the most part, be prepared to handle at least 12′ material.

For a wall that is 16′ long, use 16′ material if it available. Anytime that breaks can be eliminated jump on the opportunity.

Don’t forget about other material needed for installation. This may include flashing, trim, and nails. In some cases, these materials can amount to a cost of more than the siding itself.

Prices may vary widely from state to state on certain products such as Cyprus. Be aware of cheap prices. This can simply mean that many boards which should have been discarded were not. It is a great deal of work to go through so much material just to find something useful.