Fiber Cement Claddings

Fiber Cement Building Products Fiber cement building products are not new, but there has been a resurgence of the product in recent years in some new or re-configured products, arising out of demand for durable, low-cost cladding materials that avoid some of the disadvantages of other low cost claddings. Fiber cement products are commonly used for cladding applications in residential and commercial construction, and are evaluated alongside wood or vinyl cladding materials. Below is a list of advantages and disadvantages of the product:

Advantages:
Dimensionally stable
Holds paint well
Extremely long warranties
Abuse and impact resistant
Non-flammable
No off-gassing/VOCs
Can be cut with woodworking tools
Can be nailed close to edge
Limited accessory products (trim, decorative profiles, etc)
Suitable for many retrofit applications
Opportunity for overall project cost savings
LEED-friendly

Disadvantages:
Heavier than wood and vinyl products
Lack of experienced installers in some regions
Greater machine tool wear when cutting
Must be painted
Lack of familiarity among owners and industry
Limited range of sizes and shapes (typically only duplicate wood siding dimensions)
Limited trim and decorative options
Associated negatively with other composite products including cement asbestos shingles, MDF siding, and other pressed-fiber siding products

Related materials:
Cement asbestos shingles – No longer in use. Product can be seen in many areas where it has been installed for decades. Major disadvantage is friable asbestos fibers if shingles are chipped or broken.
Hardboard siding – Made from wood or paper fibers bonded with resin and pressed to siding shapes. Absorbs moisture and deteriorates rapidly, especially if not installed properly. Not in common use any more for that reason.
Wood siding – Traditional material, becoming more expensive as timber sizes and stocks decrease. Insect and weather resistant species (cedar, redwood, etc.) are especially hard to find and are expensive. Material must be painted or stained on all sides for long-term durability. Requires periodic refinishing to maintain weather resistance an appearance. Tendency to swell and shrink as weather changes.
Vinyl siding – Lowest cost siding material. “Look of vinyl siding” not appealing. Requires no painting. Tends to become brittle over time, and damages easily. Certain colors tend to fade in sunlight. May warp and deform in high heat. Expands and contracts with temperature changes. Materials give off VOCs.
Aluminum siding – Light weight. Requires re-painting. Expands and contracts with temperature changes. Dents easily. Used less commonly now than in the past.
Composite stone panels – Typically not included in comparisons with cement siding products, more common for commercial applications. Similar product composition however – composite panel composed of stone dust, resin, and reinforcing fibers.

Applications:
Most common applications include residential clapboard siding in lieu of vinyl or wood, especially useful in extreme environments with high humidity, extreme temperature variations, and storm damage-prone locations. Also used in areas expected to receive abuse. Because this is a manufactured product, it should be possible to introduce a greater range of material sizes and shapes to speed introduction to the commercial sector to move beyond the residential siding market. Its potential non-traditional siding profiles, low cost, along with its long service life and abuse resistance make is an attractive product for school construction and other institutional building types.

Caveats:
Owner opposition to using a “new” product could also limit acceptance in some areas. Installers who are not familiar with the product may bid higher. The material is well warrantied so risk is minimal for owners, and the cement fiber products in one form or another have been in installed for decades and have performed well.

AGB 7/2004