Solarium Construction Oxford MS
Remodeling with the Sun
The solarium addition opened the house to the outdoors, and in the process made the kitchen a wonderful place to dawdle any time of the year.
Sun Solutions, Challenges
Our house was ideally suited to take maximum advantage of a solar addition. The biggest walls of the ell face north and south. So during mid-winter, when the sun sits some 23 degrees above the horizon for less than nine hours per day, we still get the maximum solar benefit possible. In the summer, with the sun high and mighty for more than fifteen hours a day, the efficient construction and high-quality materials used in our solarium minimize any potential for overheating. Thus, a solarium made perfect sense in our remodeling plans. Most homes are not so well-oriented. Depending on your location and other factors, a solarium can be beneficial even on an east- or west-facing wall. However, it may also be a net loser of heat, too. You need to analyze your situation carefully. In any case, a solarium on the north side of a home is bound to be a net loser. At some latitudes and in most two-story homes, you wouldn't even see the sun shine through your one-story, north-facing overhead glass, much less the vertical glazing. With little light and a net heat loss, a solarium on the north side makes no sense. Another element working in favor of our solar addition was the thermal efficiency of our home. Built in 1986 while the energy crisis of the 1970s was still fresh in everyone's mind, the house's six-inch-thick walls were well insulated to an R-value of 19, while the ceilings were insulated to R-30. Windows were top-of-the-line, double-pane, low-E glazings with tight vinyl-lined tracks and vinyl-clad wood sashes. All doors were factory hung and included external storm doors. Our heating system - oil-fired hydronic radiant heat with help from a woodstove - was more than sufficient before the remodel. In short, the ell in particular and the house in general were energy efficient by any measure and a good candidate for a solarium. It's important to assess your home's current heating load and thermal efficiency accurately before proceeding with a project like ours. Many power companies and some heating fuel dealers offer free assessments of your home's thermal needs. Some will even help you with the siting of the solar addition. Of course, residential architects and engineers will analyze solar and other related considerations for a fee. Either way, it's money and time well spent. Solarium cooling is also important, even in northern states. Farther south, it's a crucial consideration. Again, good basic glazings and frame materials help, as well as lots of ventilation. We calculated that sliding windows on the south and east sides of our solarium, plus the deciduous shade tree at the southeast corner of the structure, would provide enough ventilation and shade to keep our hot summer days (both of them!) manageable. Farther south, roof vents and exterior shade curtains may be necessary. Consult with your solarium-products provider before proceeding. Finally, with the solarium solidly sketched into our kitchen renovation plans, we added a deck surrounding the new addition. An exterior door in the solarium for easy access to the deck, plus a gas grill, was like getting a seasonal kitchen added on to an expanded version of the first.
Newman's knees to the rescue
As most renovation contractors will concede, expanding an existing opening on an exterior wall is fraught with problems. Our original 5- by 6-foot bay window had to be replaced with a 7- by 10-foot walk-through opening to integrate the solarium/dining room properly with the rest of the kitchen. Unfortunately, when exterior wall openings are expanded, it's common practice to reduce the vertical height of the opening to allow for bigger header timbers to support the floors and roof above. For us, this would have required replacing the window's 2x6 headers with 2x10s, making a minimum vertical height of 7 feet impossible. We had to figure out a way to keep our 2x6s in place, but still ask them to carry a heavier load. In a situation like ours, a renovator might suggest installing diagonal braces at the corners of the opening. Structurally, that's fine, but once you've klunked your head on one of those diagonal braces, you begin to think there has to be a better way. First, we considered an engineered/laminated timber, rounded to fit into the corners and remain out of the way. This solved the klunking problem, but when the quote came in at $1,000 for each curved brace, the limitations of our budget ruled it out. While still trying to figure the problem out, we went to a boat show in nearby Portland, Maine. There I met Newman Gee, a St. Albans, Maine, woodsman and part-time farmer who said he had the solution for me. "What you need," he said, "is a natural knee." As it turns out, cutting knees from hackmatack trees was Gee's main business, and the solution he suggested was perfect for us, both aesthetically and financially. For the uninitiated, a naturally grown hackmatack knee is part of the tree's trunk. A knee is cut from the point at which the trunk meets the ground and the main roots spread out horizontally. Obviously, Mother Nature created this arrangement with a lot of inherent strength in the structure. So, although hackmatack is technically a softwood, a hackmatack knee has the structural integrity to meet the demands of the job. In fact, until the 1920s, Maine had a thriving hackmatack knee industry that provided products for the shipbuilding industry and industrial construction. They are commonly found in mills and warehouses where tremendous overhead loads are supported by natural knees. The knee I bought from Newman was six inches thick, which made it a good candidate for slicing in half and having matched supports at the corners of our new sunroom opening. Newman cut the knee in two for me, adding nothing to the $250 charge for the knee itself. Shaping a rough knee into the support structure took a couple afternoons of work with a drawknife, saws and sander. The finished product was lag-bolted into place, adding just a touch of nautical flair to the entire project, which is in keeping with the rest of our coastal home. It also fit in nicely with the timber-frame basics in the rest of the house. (For more information or a knee catalog, contact Newman Gee at the Lucky G Farm, 281 Hartland Road, St. Albans, ME 04971 or call (207) 938-2380 or visit www.newmansknees.com)
On to the sunroom
Once the problem of the opening was settled, I began work on the foundation for the sunroom. At the two corners of the foundation, we used pressure-treated wooden posts anchored to the solid granite ledge that's underneath our entire house. I doubled up the pressure-treated 2x10 sills after the sunroom installation contractor explained how important it is to have a solid foundation. Any movement, he said, will compromise the integrity of the seals around the glazings. We walled in the space underneath the sunroom with pressure-treated planking, along with rigid foam insulation, then framed the sunroom floor and insulated to ordinary building standards. Choosing the right glazing and supporting framework is critical to getting the most out of any solar addition. The decisions generally boil down to controlling solar gain during the day and heat loss during the night. Before you decide, though, there are some basics to know. Nearly everyone knows what the Egyptians found when they perfected glassmaking in 1500 B.C.: Allow sunlight to pass through a transparent medium into an enclosed area, and the enclosure's temperature quickly moves well above the outside air temperature. Solar engineers have improved on this basic concept so much that it's now possible to construct a solarium in which the enclosure's temperature is almost completely under the passive control of the materials used. Of course, almost under control means heat gains and losses are tied to how you treat that sunlight streaming through the glass. Window manufacturers take this into account when making their products. They know that regardless of where you live, the sun's light presents problems that can be divided into two categories: summer heat gain and winter heat loss. In summer the sun's ultraviolet, infrared and visible light present different problems. Infrared radiation is responsible for the heat gained in any solar enclosure. Ultraviolet radiation is responsible for sunburns and faded colors on rugs, furniture and walls. Visible light is responsible for the glare that can make it hard to see an object's true color and form. Obviously, in the summer it's important to minimize the effects of all three. Different approaches to glass construction will allow the three components of sunlight to work their will to varying degrees. Likewise, the heat trapped in solar enclosures will remain trapped to varying degrees, again depending in part on the construction of the glazing.
Choosing the right glazings
Just as different insulation (fiberglass, foam, cellulose, etc.) has different R-values, so do different glazings. As you might guess, the more efficient glazings are more expensive, sometimes running two to three times the cost of the least efficient glazings. The framing for solarium glazings is usually a choice between extruded aluminum and laminated wood. Sometimes laminated wood with a vinyl covering is available. The choice is critical, because even the best glazings on a poorly insulated framework will leave your solar enclosure cold in the winter. Wood, of course, is a natural insulator, with an R-value of about 1.25 per inch. With a 4-inch-thick framing, you can expect an R-value of about 5. On the other hand, extruded aluminum has an R-value very close to zero. So it's very important to make sure your extruded aluminum framework is foam-filled. Done properly, a two-inch, hollow aluminum support extrusion can have an R-value of nearly 10. Unfortunately, filling aluminum extrusions is not always done properly. When spraying foam into a cavity, hasty work makes it easy to create voids. These voids can decrease the R-value in the area of the void by half or more. There is no easy way to tell if there are voids in an extrusion until after the structure is up and it's mid-winter. Then the voids show up as places where frost condenses on the inside of the extrusion - not a very comforting vision on a January day in your solarium. The best defense against this problem is choosing a solarium manufacturer who has been in the business at least 10 years and offers a warranty for more than five years. Two final words on solarium efficiency: Sealing counts. The method by which the glazing is held and sealed in the framework is crucial to its being both thermally tight and waterproof. Both wood and aluminum frameworks will move with seasonal heating and cooling - even daily heating and cooling. Wood is also sensitive to seasonal wet/dry cycles. Over time (five years or so), these movements can compromise inadequate sealing methods and materials. So it's best to be certain your solarium manufacturer has been using their sealing method for at least ten years and the company will stand behind it for a similar length of time.
Island changes the flow
Back in the main area of the kitchen, we solved traffic problems with a little creative cabinetry. The mid-kitchen island provided a central, informal eating and preparation area. However, it presented some technical problems during installation. Originally, the cabinet with the countertop over it provided the informal breakfast nook and some storage cabinets. Because all of our kitchen cabinetry is made from rare American elm lumber, it was necessary to use the old breakfast nook cabinet in the new island. Additionally, the cabinet had to be expanded to accommodate a dishwasher - normally a simple procedure except when you take into consideration the American elm's acoustic properties. It conducts sound very well. Thus, the space for the dishwasher had to be expanded to accommodate extra sound-deadening insulation. On top of the island cabinet, a greatly expanded countertop was sketched in. Unfortunately, the overhanging portion of the island's countertop exceeded the manufacturer's specifications for an unsupported overhang. Steel or aluminum strongbacks screwed to the underside of the countertop were offered as solutions, but we thought they'd look too industrial. Instead, I laminated some gracefully curving elm support brackets that are perfectly functional yet remain out of the way for anyone sitting at the overhang. Once in place, the island's mere presence separated the formal dining area in the solarium from the preparation and cleaning area of the sink and stove. All that remained was to move the refrigerator a little closer to the prep area and create more storage space closer to the prep area. We did this by building a big pantry and recessing the refrigerator into it. Shelf space was created floor-to-ceiling to the north of the refrigerator where a pocket door allowed maximum use of the interior space. Over the refrigerator, more cabinet space was built into the wall. In short, the pantry space is used to the max. Of course, when you give someone the kitchen they always wanted, it's tempting to spend as much time as possible there. Melissa's file cabinet and writing desk soon found a home in the vacant southeast corner of the kitchen. Just as we intended, the kitchen has become a place to dawdle and feel as if you're outside, regardless of the time of the year or occasion. It's definitely a kitchen for all seasons.