Climate control

Just suppose an architectural firm from Seattle has been given the assignment to design a structure for a client in Reno.

They like the rich look of solid wood exteriors.After all, creative use of wood has won the firm many design awards for projects in Seattle and Portland.

Reno should be no different.

Listen carefully.

That sound you hear is the shaking of heads by architects and builders in northern Nevada who know better.

The wide range of climate changes combined with low humidity has brought sorrow to many building designers unfamiliar with which materials will hold up here and which ones will not.

"Architects and contractors do need to understand this region," says Martin Harsin of the Worth Group, a Reno design and build firm.

The temperature swings in northern Nevada can range from an average of 35 degrees daily to as high as 60 or 70.

It dictates how far down a builder must place footings for a structure as well as how deep utility pipes must be buried, and, perhaps more importantly, the kind of exterior cladding system the architect selects.

Harsin says most architects and builders in northern Nevada design for climate conditions, sun and wind patterns.

"We choose to work with those climatic conditions, not to fight them," he says.

Ken Bartlett, principal for Bartlett Architecture in Reno, concurs.

"Codes here say we must design structures that can withstand wind speeds of 85 miles an hour and up to 105 miles an hour for a threesecond gust.

These are conditions that are not found everywhere," he says.

Roofing materials are impacted by climatic conditions as are materials used on the exterior of structures.

"We are seeing a lot more requests for flat roofing systems," says Bartlett.

One reason, he and others say, is that a slightly pitched roof increases the overall cost.Until last January when the Reno area found itself buried in up to seven feet of snow in what was described as a 100 year snow event, recently built structures with flat roofs fared well.

"What we did find, though," says Bartlett, "is there were not sufficient downspouts to drain away the snowmelt.

Today,we are designing more downspouts into our roofing systems."

It wasn't that long ago, says Jeff Klippenstein, a partner in the Reno architectural firm of Hershenow & Klippenstein, that one saw lots of wood exteriors in homes.

"We used to see exterior wood siding from some builders, but the caulk joints were brutal.

The climatic extremes would cause them to expand and contract until the caulk finally gave up and separated," he says."Today, you are seeing a resurgence of stucco used on the exterior walls."

One reason, he says, is that stucco used 20 or 30 years ago was concrete based.

Builders would paint over the stucco whatever color the client wanted.

But climatic conditions often caused the stucco to crack and peel.

Today, the stucco is acrylic based with the color already added in.

"It will expand or contract regardless of the climatic conditions and is much more forgiving,"Klippenstein says.

In large commercial jobs, tilt-up concrete is favored and is often covered with an insulating layer of some material such as polystyrene.

This buildup of thermal mass with concrete keeps the interior of the structure cool during the warm summer days, yet the heat from the concrete will radiate inside during the evening when the outside temperature cools by some 30 to 40 degrees.

Such design in the Truckee Meadows also helps keep energy costs down.

One impact is the ability to use evaporative cooling systems which are much cheaper to install and to operate, especially in large manufacturing,warehouse or distribution businesses.

Worth Group's Harsin says many architects from outside northern Nevada choose to work with local building contractors.

"They have the experience with certain materials," he says."We are a design/build firm and whenever we come across a different material that might be applicable,we will call in contractors who may have had some experience with that product."

Harsin realizes wood is a big design commodity in some parts of the country, especially the Pacific Northwest.

"It is a natural material with moisture content, but if you ship large wood beams down here, say, from Oregon, and they have been stacked four feet but haven't been cured in this climate, those beams when used in the structure will begin to dry out.When that happens, the members will shrink or swell and other adjoining materials will begin to be affected," he says."Then someone has a big problem."