Craiker’s Corner: Green roofs could be a boon to wine industry construction

Could environmentally friendly designs be an asset to viticulture?

I have a green roof. It’s green composition asphalt, except in the summer when the six overhead redwood trees drop all their needles, and the roof turns brown. But I’ve always been intrigued with the advantages of providing a vegetated green plant-based roof.

Green or vegetated roofs are loosely defined as a living plant cultivated space on top of a human-made structure, such as a home, office or warehouse. Typically, they are above grade, but you might consider a wine cave bored into the ground a green roofed structure. Green roofs can provide a wide range of public and private benefits and have been installed in countries all around the world.

This is not like planting a garden or park on our roofs, although multiple types of herbs plants and fruits often are grown safely and to the advantage of the building owners. Green roofs don’t just look edgy, they are also highly energy-efficient and environmentally friendly. They’re really cool ― literally.

Building owners can reap good financial returns on their investments while providing significant economic, environmental and social benefits both in cities and in our communities.

However, green roofs can be complicated. They vary by the region, solar orientation, building design and the complexity of construction. They require high-quality waterproofing, a rigorous water repellent system, superb drainage, layers of filtered cloth, and careful attention to details. Some green roofs can be in shallow planter boxes or pottery and require independent drainage, separate from traditional roof gutters and downspouts. Using interlocking grids or loose portable containers can be installed independently.

It’s not necessarily easy but it has great benefits to our environment and our battle against climate change. Green roofs can provide these benefits:

• Stormwater management by slowing rainwater dumping into gutters, downspouts and into the earth.
• In summer, green roofs can reduce heat gain by 25%—40%. In the winter, green roofs can reduce heat loss by 40%.
• For urban areas, green roofs will reduce the urban heat island, affect. The light absorbed by the plants can be converted into growing energy, not building heat.
• Covering large warehouse and building areas in urban areas can reduce their heat gain and reflectivity substantially.
• Plants on these green roofs can improve air quality potentially, they can also filter noxious gases, although complicated.
• Green roofs can reduce noise in urban areas or near airports, such as the growing industrial complex around Napa’s airfield.

Interestingly, San Francisco was the first United States city to mandate that new construction projects require solar or vegetated roofs. This mandate requires that between 15% and 30% of roof space is either vegetated or solar.

Since such improvements, either as new construction or renovation, could qualify as sustainable and energy efficient, there are some tax incentives. The Energy Policy Act of 2005, currently in place, offers tax incentives of up to $1.80 per square foot for buildings improvements including solar panels and vegetative roofs as well as various other innovative technologies that decrease the effects of greenhouse gases. May not sound like much but it all adds up.

Also, the Inflation Reduction Act of 2023 provides numerous financial incentives for purchasing climate-friendly technologies and opportunities for businesses. I’ll leave it to the bean counters to figure it out.

Green roofs might seem like a hippie far-out concept, but it could be a great benefit to the Wine Country. Wine storage does not have to be exclusively in highly air-conditioned warehouses, wine caves or underground vaults. Instead, providing green roofs could have significant advantages to our wine industry.

There’s no question that green roofs are heavier and require more structural support, sometimes up to 25% more, but for new design buildings, this is easy.

Such structures don’t have to be concrete it can be combination of wood and steel frames with ample slope for drainage and excellent waterproofing.

Rather than spending over $1,000 a square foot to bore a cave for wine storage, the cost could be one-third if a practical warehouse is built with a living, breathing green roof. At the same time, one can achieve LEED status with reduce carbon footprint and potentially lower maintenance cost, if properly installed.

Greening our North Bay winery roofs could be a great PR strategy. PR as in politically righteous. We could turn lemons into limoncello. Forget the lemonade.