There are plenty of building materials that are used for sidings; wood, fiber cement, metal, brick, stone, vinyl, hardie board, composite, but which is the best siding for house walls and which is the most eco friendly siding material? The best siding for house walls that is eco friendly too is wood, but there are pros and cons to every material.
What is the best siding for house exteriors?
The best siding for house exteriors is decided by a combination of a number of factors including affordability, fire resistance, longevity, maintenance requirements and energy efficiency. All the materials in our list are good for sixty years.
Wood is an eco friendly building material that can be sustainably sourced. It is aesthetically pleasing to look at and has been a favorite for decades. But, homebuilders use wood siding less than they used to. It used to be installed on around 60,000 new homes a year and now that is less than 17,000 new homes (US Department of Housing and Urban Development).
Part of the reason for this is cost and part of the reason for this is maintenance. Wooden clapboard siding costs around twice as much as vinyl siding, so if sustainability is not a focus for your home, vinyl is the no brainer.
Wood sidings need regular repainting or refinishing and they need protection against insect infestation and moisture damage. Thermally modified wood is rot and insect resistant. Treating it with heat and water reduces the moisture content. This processing makes it up to 50% more expensive than untreated wood. And it still needs some maintenance (Build with Rise).
A ½ inch wood siding has an average R-value of 0.81 (PSU). What is an R-value? The R-value is a measurement of the resistance to heat flow in a material. This higher the R-value the better the insulation or thermal performance.
With wildfires on the increase around the world due to climate change, fire resistance has to be a consideration for every homeowner looking to replace siding. Wood siding is not naturally fire resistant. Treating it with chemicals can make it more flame retardant. Brand names include Master Flame, Flamex and Phos-Chek Fortify.
Remember that protecting your siding from flames does not stop a fire from entering your home via the roof and soffits. The Federal Emergency Management Agency (FEMA) does not recommend wood siding that has not been fire retardant treated as a construction material on houses within a wildfire zone.
Vinyl siding is being used less for new build homes. Installation is about half what it was two decades ago at 28,000 new homes. Vinyl siding was initially popular because it is cheap. It is also low maintenance, as it is made of PVC, a type of plastic.
Vinyl siding alone has an R-value of 0.61 but insulated vinyl siding has an R-value of 2.0-3.5 which is high (Progressive Foam). Insulated vinyl siding is siding that has contoured foam filling the void between the siding and the wall. Installing insulated vinyl siding could reduce your energy bills by as much as 16%.
Vinyl siding is not fire resistant and can melt, allowing a fire entry to the fabric of the building. The Federal Emergency Management Agency (FEMA) Homebuilders Guide to Construction in Wildfire Zones does not recommend vinyl siding as a construction material on houses within a wildfire zone for this reason. They do say that a layer of gypsum might give a house some protection during a fire.
Fiber cement siding (also known as Hardie board)
Fiber cement siding is a mix of cement, sand and wood fibers. It is sometimes referred to as Hardie board siding or James Hardie siding. James Hardie is a manufacturer of fiber cement siding.
Second only to brick sidings, construction firms use fiber cement for cladding in 8% of new homes. Its popularity is due to the fact that it is fire resistant, durable in storms and bad weather, insect & pest resistant, and rot & damp resistant. James Hardie fiber cement siding materials are graded class 5 “flood resistant materials” by FEMA (PDF).
Fiber cement siding can be ordered pre-painted and finished. The main disadvantage of fiber cement planks is that the installation needs to be done by an expert with specialist equipment and this can add to the cost. It makes fiber cement siding more expensive than wood siding or vinyl siding. Fiber cement siding also needs maintenance; repainting and caulking.
Fiber cement siding has an R-value of only 0.5. Like vinyl siding and wood plank cladding, it needs insulation between it and the wall, which can improve the rating.
Fiber cement siding is estimated to have a higher resale value and recoup 76% of installation costs, compared to vinyl siding which recoups 63% of installation costs – National Association of Realtors (PDF).
Is fiber cement siding the bet siding for house walls?
Brick siding is the most popular finish on new homes. Brick siding needs little maintenance. You might want to give it the occasional pressure wash. Brick siding is regarded as fire resistant by FEMA but it is not permitted in some states, like California, due to the risk from seismic activity.
Brick is more expensive than wood or fiber cement and it is a lot more expensive than vinyl. It has an R-value of 0.8 making it the most thermally efficient material on this list, aside from insulated materials (Arch Toolbox).
Eco friendly siding materials
While you are researching what is the best siding for house ideas, you might want to consider what makes an eco friendly siding material? There are five factors that make up an eco friendly siding material:
Raw materials – what is needed to make the sidings and is that material sustainable and renewable?
Manufacturing process – how much energy and water is used in the manufacturing process of the siding?
Transport – how far does the raw material have to travel to get to the manufacturer and how far do the components or completed goods need to travel to the end consumer?
Installation – what is the environmental cost of installing the siding?
End of life – can the materials used in the siding be recycled? If not, can they be disposed of safely and will they degrade?
The National Institute of Standards & Technology have measured each of these. They rank the siding materials for global warming potential from lowest to highest:
- Vinyl siding (generic)
- Aluminum siding (generic)
- Insulated vinyl siding (generic)
- Cedar wood siding (generic)
- Polypropylene siding (generic)
- Stucco siding (generic)
- Fiber cement siding (branded CertainTeed Weatherboard)
- Bricks & mortar siding (generic)
The wood siding is in 4th place because of the inability to reuse the material at end of life. That’s why vinyl and aluminum score so highly. If green living is your aim, wood siding might be desirable over vinyl as the wood can be sustainably sourced and it is biodegradable.
Vinyl siding contains PVC which is toxic in certain conditions like a fire, although the risk is small and it can be recycled which reduces the raw material costs (Consumer Reports). As it is not biodegradable, if it is sent to landfill there is a risk that plastics can leach into the local environment, so it should be recycled whenever possible. Polypropylene is similar, in that it contains plastic but can be recycled.
Aluminum siding can also be recycled or sold to a local scrap merchant. Aluminum is a finite resource and could in theory run out.
Fiber cement siding can be recycled after use. It gets broken down and reused as clinker or cement that can be used for construction (RIBA).
Stucco and brick sidings are not recyclable. Despite this brick is very popular, so it still might be the best siding for house walls for your home.
The best siding for house cladding
The best siding for house cladding will depend on where you live. If you live in a fire zone or an area prone to flooding, fiber cement siding will be your best option as it is flood resistant and naturally fireproof.
If sustainability is your focus, the best siding for house walls might be a product that is more natural like wood siding. This does mean you will pay more and have some maintenance requirements, but it avoids plastic. If you do choose aluminum, vinyl or polypropylene, always recycle it safely.