The industry's solution for heat shields PermaBASE cement boards are the industry-preferred choice. Installation-ready and easy-to-use, PermaBASE® cement boards eliminate the need for field fabrication, saving time while allowing for enhanced performance and wood-burning stove placement closer to the wall.
Cement board typically has a thermal conductivity (k-value) ranging from 0.18 to 0.35 Watts per metre-Kelvin (W/mK). Compared to concrete (1.0-1.8 W/mK), this relatively low thermal conductivity allows cement boards to provide some insulation value.
A high density cement board reinforced with inorganic fibers, NAD-11 is suitable for applications requiring continuous operation in temperatures up to 500°C (932°F). NAD-11 is dimensionally stabile, non-combustible, chemically inert, and it retains its mechanical strength at temperature.
If there is combustible material behind the cement board, such as direct contact with wood studs, this is still a combustible wall. Cement board is actually a very good conductor of heat. The clearance would be measured a minimum 12 inches from stove surface to combustible studs with a approved ventilated shield.
Some high-end rigid heat shields are made out of either aluminum, gold or composite, with most examples including a ceramic coating to provide a thermal barrier, which improves heat insulation. The flexible heat shield are normally made from thin aluminum or gold sheeting, most commonly sold either flat or in a roll.
Fire Resistance of Cement Board
They can endure high temperatures without combusting immediately, providing a critical buffer that slows down the fire's progression and gives occupants valuable time to evacuate safely.
Replacing the back wall with heat-resistant materials, like heat-resistant stones or a specialized wood stove heat shield, can be cumbersome and aesthetically displeasing. A simpler, more elegant solution is to use a cast iron fireback as a heat shield for the wood stove.
PermaBASE Building Products created a wall heat shield system that can be made of ½" PermaBASE or ½" PermaBASE PLUS® cement boards — both of which are listed by Underwriters Laboratories Inc. for use with UL-listed solid-fuel and fireplace stove.
H91 Cement Board Physical Properties:
Operating Temp - 1292º F/700º C. Compressive Strength - 16,675 psi ambient 15,310 psi (24 hrs @ 700º F) 14,020 psi (24 hrs @ 1000º F) Electrical Strength - 1.83 Kv/mm in air @ 200° F.
HardieBacker® 12mm cement backerboard is fire rated class A1, meaning the product is non-combustible. HardieBacker® 12mm cement backerboard is CE approved and BBA certified since May 2004. Hardiebacker say it is fine for up to 100 degrees centigrade (it will not set on fire but can crack).
Others say their product will last between 50 and 60 years. Fibre cement cladding is known for its durability. It can stand up well to extreme temperature changes and extreme weather. You don't need to worry about it cracking under pressure.
Mat-faced gypsum cover boards are increasingly used as a cement board alternative because they are lighter and easier to install. There are also performance enhancing benefits that mat-faced gypsum cover boards have over traditional cement alternatives.
Cement board siding is a poor insulator and absorbs a considerable amount of heat in warm months.
Flat panels that get wet due to precipitation or condensation will precipitate calcium/efflorescence, & will result in permanent damage that would not occur when properly stored or in proper use.
Heat shields have traditionally been fabricated from copper and aluminum, when the highest possible thermal conductivity is required, and to a lesser extent from stainless steel.
By far the most effective heat shields are the air-cooled type. These shields are constructed with a sheet of 24 gauge or thicker sheet metal, or 1/2" or thicker cement board, with 1" of air space behind the shield and around the perimeter to allow free airflow.
HardieBacker® cement board has been evaluated by the BBA and approved with certificate no. 04/4100. The products meet the European standard for fibre cement - EN 12467 and its reaction to fire, in accordance with EN 13501-1, is A1,S1-d0. The product is therefore classified as fully non-combustible.
So about 75 pounds for a 4x8.
Superior Strength and Durability. DUROCK Next Gen Cement Board's high compressive strength offers damage and impact resistance while maintaining dimensional stability and does not delaminate. Fire Resistance. DUROCK Next Gen Cement Board is a non-combustible panel and meets CAN/ULC S114 and ASTM E136.
Aluminium foil is very often laminated on carrier material for strong heat protection. Thus, the light weight and good heat protection can also be optimally used, for example, by the fire brigade and fire protection.
Coated fabrics are often used as heat shields and for protective purposes. Coatings can be made from neoprene, silicon, ceramic or others and are also UV, chemical and abrasion resistant. Heat shields made from heat resistant fabrics are highly durable and are able to be used in extreme environments.
Louvered Blinds
When completely closed and lowered on a sunny window, highly reflective blinds can reduce heat gain. Horizontal slat-type blinds can also be adjusted to block and reflect direct sunlight onto a light-colored ceiling.