More homeowners are building to the principles of Baubiologie, also written Bau-Biologie or Bau Biologie and known in English as building biology. The tradition began in Germany after the Second World War, when architects and researchers started asking how buildings affect the people who live in them. The Institute of Building Biology + Sustainability (IBN) in Rosenheim condensed that work into 25 guiding principles, and the architect Helmut Ziehe brought them to North America in the 1980s.
We hear from these homeowners often. The question usually comes down to this: does a metal roof belong on a building biology house? We are a German-tradition sheet metal shop, so we have thought about it for a long time. Here is our honest answer.
What does building biology ask of a roof?
The 25 principles cover the site, indoor air, materials, moisture, light, sound and electromagnetic fields. A roof touches several of them at once. Building biologists generally look for:
- Materials that are natural or unadulterated, with no harsh odors or chemical emissions
- A building envelope that manages moisture well, so mold never gets a start
- Durability, because a long-lived building wastes less
- Materials that can be reused or recycled at the end of their life
- Thoughtful handling of anything that affects electric and electromagnetic fields
The IBN itself admits that real projects cannot always meet every criterion. The goal is to make the best choice your site, design and budget allow.
Is a metal roof good for a building biology home?
No roofing compounds in the living envelope. Asphalt shingles are a petroleum product. A properly detailed sheet metal roof is formed and seamed metal. Our panels and shingles are joined mechanically: folded, locked and fastened with concealed clips. There is far less reliance on adhesives, mastics and caulk, which tend to fail early and which some building biology clients prefer to avoid.
Durability. A well-built metal roof can outlast several asphalt roofs. Building biology treats durability as an ecological virtue, and so do we. Every roof you never have to replace is a pile of waste that never reaches a landfill.
Recyclability. Steel is among the most recycled materials in the world. At the end of a very long life, a metal roof goes back into the stream.
Moisture management. Mold prevention is central to building biology. A metal roof sheds water and snow quickly, and when it is installed over a ventilated assembly, air moves beneath the metal and carries moisture away. Ventilation and underlayment choices matter as much as the metal itself, so we discuss the full assembly on every project.
Do metal roofs affect EMF?
Some building biologists are cautious about metal roofs, and you deserve a straight answer about why. A large metal surface is conductive. If it is not properly bonded to ground, it can carry electric fields from nearby wiring, and it can change how radio signals reach the house.
This is not a reason to rule out metal. It is a reason to plan for it. If electromagnetic fields are part of your building biology goals:
- Ask your electrician and your building biology consultant how the roof should be grounded and bonded to the house system
- Plan wiring in the attic and upper floors with the roof in mind
- Have a qualified building biologist take measurements once the house is built
We are happy to coordinate with your consultant and electrician on any project.
What about metal roof coatings and finishes?
Metal is only part of the story; the finish matters too. Our galvalume products carry a metallic coating of aluminum and zinc that protects the steel. Painted finishes vary by product and color. If finish chemistry is important to your project, ask us for the data sheets on the options you are considering, and share them with your consultant before you choose.
Metal roofing options for a Baubiologie home
Spengler Industries fabricates architectural sheet metal in the tradition of the German Spenglermeister. For building biology homes, two of our products are worth a look:
- The diamond shingle, a traditional European pattern with a long history on roofs and walls
- The Quadro panel, a clean, modern profile for roofs and wall cladding
We don’t believe in one-size specifications. Every roof is different, and we work through the details of each one with the homeowner, the architect and the installer.
Building biology metal roof FAQ
Can a metal roof be part of a Baubiologie home?
Yes. Metal is durable, recyclable and installed without asphalt or roofing compounds. Plan the roof assembly, grounding and finish together with your building biology consultant.
Do metal roofs need to be grounded?
Requirements depend on your local code and your electrical design. Building biology consultants usually want the roof’s grounding planned from the start, so bring your electrician and consultant in early.
Does a metal roof attract lightning?
No. A metal roof does not make a strike more likely. If lightning protection matters for your site, ask a lightning protection specialist about a system for the whole house.
How long does a metal roof last?
A well-detailed metal roof can outlast several asphalt roofs. Ask for the expected service life of the specific product and finish in your climate.
What should I ask a roofer before choosing a metal roof?
- How are the panels or shingles joined, and how much sealant does the system rely on?
- Is the roof assembly ventilated, and what underlayment do you recommend?
- How will the roof be grounded and bonded?
- Can I see data sheets for the coating and finish?
- What is the expected service life, and what maintenance does it need?
A good roofer should be glad to answer all five.
Talk to us
If you are planning a building biology home and want to talk through a metal roof, call us at 801-462-5264 or visit www.spenglerindustries.com.