Prefab, or prefabricated construction, refers to a building method in which homes get built mostly in a factory then shipped to the site for final assembly. In this Q&A with Green Home Gnome, Method Homes explains what the benefits of prefab homes are and how they stack up to conventional and other forms of green construction.
What are the main benefits of prefab homes compared to conventional homes?
Benefits of prefab construction abound. They include minimized waste, reduced construction timelines, limited exposure to the elements, fixed cost, streamlined skilled labour, and limited site impact:
Waste minimization – Building in a centralized location allows for the utilization of leftover construction materials while a focus on employing all materials results in overall waste diversion up to 85 percent.
Reduced construction timeline – Building offsite on a concurrent track with the beginning of the site construction decreases timelines by two-thirds or more.
Limited exposure of materials to weather and contaminants – Building in a controlled, indoor environment translates to less risk of weather damage, mold and other pollutants, making for a sturdier, healthier home.
Fixed costs – Determining prices and specification at the start of the building process removes the variability from overall building costs.
Streamlined skilled labour – Master craftsmen are paid a living wage at the factory. Labour is performed on multiple projects in a centralized factory location.
Limited site impact – Reducing the amount of time and activity on the site lightens the building process’ environmental impact.
Panelized is another efficient form of green construction and it is possible to build a tight, efficient healthy home site built. The main distinction with prefab is waste reduction and the fact the home is never exposed to the elements.
How much less construction waste do your homes typically produce and does that translate into savings for the home buyer?
We work for 80 to 95 percent landfill diversion and recycle everything. This is a cost-neutral benefit of prefab.
Is there anything that detracts from their sustainability compared to other forms of green construction?
There is about 5 to 10 percent more material used than site-constructed structures but this is offset by the waste reduction from factory building.
How much energy do your homes save compared to a conventional home?
Our baseline is ENERGY STAR and we go all the way to Passive and Net Zero energy from there.
How about length of construction. Since it’s quicker to build a prefab home, does that impact price?
Yes, this minimizes interest and holding costs as well as costs of another place to live during the build.
What is the price difference per sq. ft. between your homes and the comparable conventional home (to build in your area)?
Method’s home prices are comparable to those of similar site-built homes. We build anywhere in the U.S. and Canada. In the Midwest and Southeast site building can be less costly. In areas where labour is more scarce, remote areas and areas with short building seasons,Method’s costs can be significantly lower.
How much does it cost to ship a home (to your average consumer, not too far away)?
In the greater Seattle area, each module is approximately $1,000 to 1,500 to ship.
For the home buyer on a budget who is located far from any prefab home manufacturer, would you recommend they look to an alternative form of construction or are there ways to cut down transportation costs for your prefab homes?
Method specializes in remote sites. It often times makes sense for those located in remote areas (such as islands) to build prefab. This cuts down on transportation of materials to the site, material waste, and labour cost overruns. Prior to construction, we perform a feasibility study on the land and can then recommend whether it makes more sense to opt for site-built or prefab. If not going with the modular approach we encourage true, full panelization as the next most efficient way to build.