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Renovation can involve not only a building’s interior but also its exterior. Some of you may be thinking of adding a porch, a deck, or perhaps even a greenhouse. Others may be more ambitious and be contemplating the addition of one or more rooms to the house. We are including this section for those of you who are modifying the exterior of your building. PROJECTING TO THE OUTSIDE: DECKS, PORCHES, and GREENHOUSES A transition from outside to inside is a welcome amenity in any house. The first step is to deter mine which rooms would benefit most from having access to an outdoor space. An outdoor eating area has been a traditional favorite. This area, be it a porch (open or screened in), deck, or green house, should be within easy reach from the kitchen or dining room. Providing outdoor space next to a family room or den is also desirable. For those who enjoy privacy, a deck adjacent to the bedroom seems a likely choice. As a general rule, there is no room in the house that would not be enhanced by projection to the outside. The type of outdoor space may vary with the room. E.g., you may want to have a screened-in porch for eating, a greenhouse as part of the family room, and a deck for the master bedroom. Each of these outdoor spaces will offer a different amenity. The greenhouse provides the option of year-round use, while the screened-in porch allows you to be outdoors rain- and insect- free. The next issue to consider is that of privacy. While openness within the house is limited by every individual’s need for privacy from the rest of the family, openness to the outside is affected by the need for privacy from the street and neighbors. Older houses show more evidence of this concern than their newer counterparts. As you walk through older towns and neighborhoods, you will find many houses with front porches. (By the way, the “sitting porch,” or veranda, is considered by historians to be an American invention.) These porches serve as buffer zones between what is public and what is private. Someone sitting on his front porch becomes a part of the street life while still being in his separate, semi-private domain. This isn't the case when a person sits on the front lawn. Strangers are aware that the lawn is private property. Yet someone sitting or relaxing on his front lawn is a conspicuous element in the street scene. Generally, people will prefer sitting in the backyard, where there is more likelihood of privacy. As architects, we have found that most of our clients have wanted the outside space to be oriented toward those areas of the house most isolated from street and neighbors. Finally you should take into account orientation to the sun. While a greenhouse with a south east exposure can be a great asset to a space, one facing due west could be very unpleasant on a summer afternoon. If you have a choice of locations, try to consider which exposure will be more appropriate for your climatic conditions. (See Section 19 for additional information on orientation and the path of the sun.) Decks Decks can be constructed out of metal or wood. Wooden decks are more popular, for the simple reason that they are the easiest for the novice to build. There are basically three types of wood that can be used: cedar, redwood, or pressure- treated lumber. Any other wood would tend to rot unless constantly painted. Pressure-treated lumber is the cheapest of the three and for this reason the one most commonly used. It has a greenish tint that's not attractive at first but, fortunately, turns silver in time. Cedar is initially more attractive but more costly. When first in stalled, cedar is a warm light brown; this slowly turns into a grayish silver. Although cedar does not require an applied finish, we have found that it's most durable and weathers more evenly when protected with a stain (be it transparent, semi-transparent, or bleaching). Redwood is a handsome and durable wood that does not need an applied finish. Because it's presently very scarce, it's the most expensive of the three choices. Metal decks are more rarely seen since they are more expensive and entail metalworking skills that aren't easily acquired. In addition, people often associate metal decks with fire escapes and institutional applications. Not all metal decks need to be unattractive. Perhaps thinking of New Orleans rather than an inner-city tenement can help you visualize the possibilities of designing with metal. Before you make the final decision on using wood or metal, make sure to check with the local building department. There are municipalities in which metal decks are required by law for reasons of fire safety (usually in densely populated urban areas). Metal decks do require maintenance against rust. They have to be painted periodically with a rust-inhibitive undercoat and one or two coats of paint over it. We have found that combining wood and metal can result in a very interesting deck. Be cause metal is stronger than wood, a structural framework made out of metal can use much smaller members than one made out of wood. The result is a lighter, more delicate deck. Wood decking can be fitted into the metal framework. It can also be used to cap railings and as treads for the stairs. The introduction of these wood elements provides you with the warmth of wood and the lightness of metal. The result is a very handsome product that accentuates the best qualities of both materials. An additional advantage to this approach is that this type of deck is often accepted by the building departments requiring metal decks. The logic behind it's that the basic structure is built out of metal with wood serving only as a nonstructural, purely aesthetic element. Decks can be laid out in many different shapes and sizes. Rectangles and squares are the most popular, since they are the easiest to build. Angles and curves are generally left to the more experienced or the professional builder. Keep in mind that decks should be kept in proportion to the house and to the property surrounding it. We have seen many renovators build enormous decks that have dwarfed their houses in addition to covering most of the available open space. If the deck is up on the second floor or if you have a usable basement underneath, remember that a large deck will block the sunlight for the windows in the lower floor. A deck isn't necessarily better because it's larger. An efficiently designed deck can be more useful and attractive than an overscale one. Decks can incorporate arbors, benches, storage bins, and planters (Ill. 2). An arbor or trellis can offer shade with its rich latticework covered with vines. When space is at a premium, built-in benches give you the extra room you need. Similarly, an arbor can offer you shade and privacy in a densely built area. Storage bins are very helpful, particularly where there isn't much room to stow outdoor-related items such as gardening tools. There are a few basic points that you should remember when designing your deck. Wooden decks need posts which are usually 4” X 4”. For spans, refer to sects. 16 and 21. All wood should be kept away from the earth to avoid insect infestation. Metal decks are constructed with Lally columns as the vertical supports; these are usually 3” or 4” in diameter. The metal spans (by means of steel channels or beams) can be longer than those of wood. The railing around the deck should be approximately 36” high. Many codes mandate a minimum of 6” of space between either vertical or horizontal railings. Those of you with young children should consider the potential hazards of designing widely spaced horizontal elements in the railings. Vertical rails placed at close intervals (about 3” apart so that a child’s head can't get stuck between supports) are one of the safest designs for children. Porches Porches are a more integral part of the building than a deck, for the simple reason that a porch has a roof. This is one of the most attractive aspects of a porch. You can be outside in the rain or under the scorching sun and be protected. A porch can be provided with removable screens. During the spring and fall, the screens can be stored. In the dead of summer when bugs are out en masse, you can install the screens and have a safe haven. Removable glass panels could also be designed to allow the porch to be used during the winter months. The materials used in the porch will be determined by those used in the rest of the building. Most likely the porch, like the house, will be built out of wood. The type of wood would be similar to that of the house and would be painted or stained to match. In planning a porch keep in mind its proportions. The porch shouldn't dwarf the house but rather should complement it. Similarly, the roof of the porch should be designed to enhance the lines of the existing roof. Greenhouses In the past greenhouses were used primarily by people who enjoyed gardening or raising house plants. Now they are quite popular for other purposes. A greenhouse is often installed as an extension to a room in the house and is a welcome addition to a playroom, dining area, sitting room, or even a bathroom. A greenhouse may also be used in place of a corridor to connect two spaces. The primary advantage of a greenhouse is that the all-glass enclosure lets in light and serves as a means of bringing the outdoors in. Unlike an open porch or deck, greenhouses can be conditioned so that the space can be used year-round. In addition, if the greenhouse is properly oriented it can become a source of passive solar heat for the house. All of these benefits can be gained at relatively low cost. Greenhouses can be framed in wood or purchased ready-assembled. We don't recommend getting involved in the framing of a greenhouse since it's a rather painstaking process. The glazing needs to be cut to size and fit very carefully into the framework. To avoid water penetration, joints need to be tightly sealed with caulking or glazing compound or gaskets. In addition, you have the problem of sweating or condensation. (This occurs when warm, moist air comes in contact with cold glass.) All of the above spell a labor-intensive and problem-ridden process that can easily be avoided by buying a manufactured greenhouse. In the process of improving their product, manufacturers have solved many of the problems related to water leakage and condensation control which are inherent in greenhouse design. Prefabricated greenhouses are made of modular components. These modules or bays are approximately 2’-6” in width. The length can be customized by the number of bays that you choose. In widths, the bays range from 3’ at the narrowest to 15’ at the widest. In terms of height, greenhouses are available in models of one, two, and more stories. Greenhouse companies keep their most popular models in stock. These usually range from 3’ to 13’ in width, from three to ten bays in length, and are one or two stories high. When ordering a greenhouse, you will be asked the number of gable ends you need—that is, whether you need a greenhouse with one glass end wall, two glass end walls, or none at all. The number of gables (or lack of them) depends solely on your specific design. The two principal components of a greenhouse are the structural framework and the glazing. The frame can be made out of metal (generally anodized aluminum) or wood. Metal greenhouses offer ease of maintenance at a relatively low cost. In addition, the slender metal components give these greenhouses a light and airy look. For those who object to the “industrial” look of metal, laminated-wood greenhouses are also available. The wood framework, although heavier, offers the warmth inherent in the material. On the downside, wood, by its very nature, requires more maintenance and is generally higher in cost. If you decide on a wood greenhouse, we recommend you use those ‘made out of cedar since they tend to be more durable. The type of glazing that you choose is also important. Greenhouses can be single-, double-, or triple-glazed. Single glazing means that there is one layer of glass between you and the outside. Double glazing gives you two layers of glass with an air space sandwiched in between. Triple glazing has three layers of glass and two air spaces. Single glazing is subject to condensation problems. For this reason, we recommend single glazing only for those of you who intend to use the greenhouse solely for gardening. Double glazing eases condensation significantly and it's the on we recommend. Triple glazing is even more efficient but it's more expensive. As a general rule, greenhouses come equipped with tempered safety glass. In terms of color, the most popular is the clear glass. Bronze and silver glass are optional. There are a number of accessories available for your greenhouse. For ventilation, you can get awning windows or louvered vents. The greenhouse can have single, French, or sliding doors installed in one or both gable ends. Issues of insulation, privacy, and sun control are addressed with a variety of devices. There are insulated shades and window quilts which offer all of the above. Some types are motorized to facilitate raising and lowering. In addition, there are pleated translucent shades and mini-blinds which allow privacy and shading. EXTERIOR FINISHES and WEATHERPROOFING Those renovators who are building extensions to their homes or moving windows around should be versed in the various materials available for completing the exterior. If you are patching the existing exterior, you will want to match the material exactly. Those of you who are adding an extension will find the choice of exterior finishes dictated primarily by the materials already on the house. Combinations of different materials are also possible but should be carefully evaluated in terms of both aesthetics and maintenance. For ex ample, if your existing house is constructed of brick, it may be easier and aesthetically more interesting to finish the addition in clapboard rather than brick. First, if the existing brick is old, it's unlikely that you will match the color (and some times even the size). It may take years for your new brick addition to develop the patina of the existing house. Second, wood siding is easier and less costly to install. There are historical precedents for wood additions to brick main houses and so the combination will not be out of context. (A brick extension on a wooden house is another matter.) If you have an all-brick house and want to continue using brick, you should be careful to match, as best you can, the existing brick in color and texture. Wooden houses are easier to deal with, particularly if they are painted. Although this isn't a general rule, houses with a painted finish should have painted extensions and buildings that have wood-stain siding should have stained extensions. A rudimentary knowledge of roofing, waterproofing, and weather stripping is also important. After all, the last thing you need after going through the trouble of a renovation is a leaky roof. Exterior Wall Finishes There are many ways in which exterior walls may be finished. Exterior finishing materials may be categorized into natural and “other.” The authors must admit a strong prejudice for natural materials, which include all of the wood products, stone, and brick, over “others,” which include aluminum and vinyl-coated metal siding. This prejudice stems from the fact that the natural materials look like what they are supposed to be—that is, wood boards look like wood boards, brick looks like brick, and so on. The other products disguise themselves as something that they aren't . Aluminum is made to appear to be wood boards; plastic is cast to resemble random stone or slate. There are a number of advantages to these products, including the fact that they are maintenance-free and in some cases cheaper than what they imitate. Be that as it may, we will not elaborate on these materials. If you are eager to use them, it's easy enough to find information on their advantages and cost. In choosing among the large number of exterior finishes available, you should consider color, pat tern, material, texture, and direction of emphasis (either horizontal or vertical). In addition, there are the not so small considerations of price and ease of erection. Wood Horizontally applied siding comes in a number of styles. Two of the most popular are clapboards and beveled siding. When siding is applied horizontally, the long horizontal shadows cast along the wall emphasize the length of the house. Had these same boards been applied vertically, the emphasis would have been on the height of the building. Traditionally clapboards are painted, but they need not be. Beveled-siding boards come in lengths up to 12’. Vertically applied siding comes in tongue-and- groove boards and in board-and-batten patterns. Tongue-and-groove boards are manufactured to form a lock-and-key joint where they abut one another. In the board-and-batten style the board-and-batten style and a panel that has a vertical indentation every 12”, which is called texture 1-11. Before deciding on an exterior finish for your extension, consult Sweet’s Catalogue, the various construction magazines, the house and garden periodicals, and the folders at the lumberyard. There is a wealth of advertising literature on exterior siding. Brick boards are usually side- and square-cut. Because they have a tendency to expand and contract de pending on the weather, they can't be laid out tightly side by side. A small expansion joint is left between the boards, which is then covered up by a narrow batten strip. Vertical siding can be painted, stained, or treated with a preservative and left to weather naturally. Shingles are another category of siding materials. They are a little more time-consuming to in stall than either vertical or horizontal boards. They come in a variety of sizes, colors, and materials (from wood to fiberglass-asphalt strips). The most expensive are hand-split wood shingles; their heavy texture lends a rustic look to the house. Factory-made cedar shingles are attractive and can be left in their natural state to weather. Plywood exterior panels are rather popular. They are easy to erect and because of their size involve a good deal less work than other siding. An additional advantage is that the exterior ply wood panel can be nailed directly to the studs, thus eliminating the need for sheathing altogether. The panels come in widths of 4’ and lengths of 8’, 9’, and 10’. If the exterior plywood panel is to be applied directly to the studs without sheathing and is to act as structural bracing as well as finishing, it should be a minimum of ¾” thick. There is a large selection of colors and pat terns in plywood siding. The most popular are the If one or more sides of the house are taller than the height of the sheet of plywood siding, you may reconsider your decision to use plywood siding. Although the vertical joint between panels is easy to mask, the horizontal joint will be obvious. In addition, the horizontal joint may require metal flashing, which might detract from the appearance of the wall. Brick There are many types of brick. Some are marketed for great strength, some for unique color, and others for unusual size. Bricks are made out of clay that's either dug from underground tunnels or stripped from the surface of the earth. Essentially, the raw clay is dried, crushed into a fine powder, and mixed with water to a mud consistency. The clay is then molded into units, dried in ovens, and finally baked in high-temperature kilns. This is the age-old procedure for manufacturing the bricks you might come in contact with. Bricks are named according to the clay they are made from (fireclay or otherwise), the kind of method used in shaping the units (sand- or water- struck), the care taken in the manufacturing procedure (face brick or common), the built-in strength, or the finish applied to the face after the initial firing (glazed brick). It is likely that you will be working with face brick. This type of brick is similar to common brick but is manufactured with greater care given to color and texture. The range of colors presently available is very large. Many brickyards also carry used bricks. This is of particular value to renovators trying to match existing brick. In selecting your bricks, make sure that you are buying the appropriate grade. SW (severe weather) brick is for exterior construction in climates that combine wetness with temperatures below freezing. The second grade, MW (moderate weather), is for exterior use in dry climates that might be subject to freezing temperatures. The third classification, NW (no weather), is for interior use. Brick comes in many sizes and shapes. The standard brick size (which includes the bricks described above) is 2 1/4” high by 3 3/4” wide by 8” long. If you are matching brick, make sure to bring one along to the brickyard. It is important to consider the type of bonding you will use, the bonding material, its color, the width of the joints, and the method that will be used by the mason to “strike” the joints (Ills. 8 and 9). If you are patching brick, you may have to color the mortar to match the existing old mortar. Stone Although stone is a most beautiful building material, it would be irresponsible of us to recommend your undertaking a project that includes stone construction. The material is hard to find, expensive, tricky to cut, heavy to haul, and time- consuming to lay. There are renovators who may already have stone or partially stone buildings. Our recommendation is to get a good mason. If you live in a landmark neighborhood or in an area where there is a Landmarks Commission, give them a call. They usually have a list of approved contractors whom they recommend. Roofing Roofing materials come in two major categories, and which one to choose depends on the slope of your roof. Built-up roofing is most generally used for “flat” and low-sloped roofs. This type of roofing provides watertight protection for the roof that does not drain rainwater and snow quickly. Pitched roofs, on the other hand, shed water and snow quickly and provide a scalelike protection. We will begin the discussion with the sloped roof using wood shingles. Wood shingles and shakes are an extremely attractive roof finish. The shingles, be they cypress, redwood, or cedar, machine-finished or hand-split, provide natural water resistance with their own resins and oils. Shingles are graded no. 1 and no. 2. They are cut in standard lengths of 16”, 18”, and 24” and are bundled in random widths for purposes of design texture. The shingles come tapered and in a variety of thicknesses. Thickness determines how the shingles are laid, since they are overlapped one on the other. Usually one bundle of shingles will cover 100 square feet of roof. The disadvantages of the material are that it's combustible and relatively expensive. There are, however, some roofing systems using wood shingles that have been given a high fire-resistance rating. *There is no such thing as a truly flat roof. What is called a flat roof actually has a slight pitch to allow for water drainage. Split shingles, more commonly known as shakes, are sawed from hardwood. Because they vary considerably in thickness, in width, and even in color, a shake roof or wall adds a good deal of texture and character to the house. Asphalt shingles come either in strip form or as individual shingles .* The shingles are composed of felt (rag, wood, or mineral fiber) that has been saturated with asphalt and coated on one side with granules for color and texture. The strips come in 12” X 36” pieces that are scored to look like individual shingles. Strip shingles are laid over asphalt-saturated felt and have a high fire-resistance rating. Fiberglass-asphalt shingle strips are highly resistant to fire, rot, and decay. This type of material is applied over a layer of roof felt for roofs with a slope of at least 4” in 1’. For slopes between 2” and 4” in 1’, two layers of felt are required with a layer of hot-mopped asphalt between them. Roofing tiles, popular in Europe, aren't commonly used here, because of their excessive weight (which necessitates structuring the house to accommodate the roofing material) and their high cost. The tiles consist of baked unglazed clay and come in a variety of orange-red and green-gray shades. Slate roofs, often seen on older houses, are increasingly rare. The primary reason is the high cost of both material and labor. Like clay tile, slate is very heavy and the roof structure must be strengthened to support it. Flat or low-sloped roofs require watertight roofing comprised of bituminous substances. In built-up roofing, layers of felt and bitumen are alternated to form a seamless, waterproof, flexible membrane that protects the roof from water. The bitumens keep the felt watertight, and the felts provide support for the bitumens, which would otherwise crack under the heat of the sun. *The strips make the roof installation much simpler than it would be using individual shingles. Steep roofs finished with wood shingles often don't require felt at all because of the fortunate tendency of the shingles to shed water quickly. The lower five or six rows of shingles should, however, receive the protection of some roofing paper to prevent what is called the ice dam effect. The ice dam is created by an accumulation of melting snow at the periphery of the roof a few days after a snowfall. The snow slides to the edge of the roof and is melting. The temperatures fall and the melting snow turns to ice. If more snow should fall, this ice dam will prevent the new accumulation from sliding off the roof. When this second layer begins to melt, the water will be backed up behind the dam and may make its way through the shingles to the sheathing. Flashing Flashing consists of long, thin sections of sheet metal or flexible sections of a waterproof membrane material that are placed where two different building materials are juxtaposed. Its purpose is to prevent water from entering the joint. The flashing material is laid over the gap between the two materials and prevents driving rain from penetrating by diverting it away from the structure. Common locations that will require careful flashing details are at roof ridges and valleys, at the point where the chimney meets the roof, at window and door openings, and where the roof is penetrated by pipes, vents, skylights, etc. Be careful to provide flashing where an extension intersects the existing building. Weather Stripping Wood, metal, and other materials have a tendency to expand in warm or moist weather and to contract in colder, drier air. This presents an interesting dilemma when it comes to doors and the infiltration of cold air in winter. In the summer, the moisture in the air tends to swell a wooden door, so that it might occasionally stick in its frame. On the other hand, in the winter, when we would prefer an airtight joint between the door and its frame, the door shrinks, causing a gap that allows cold air to infiltrate. This problem is easily rectified for doors by installing metal spring strips around the doors to prevent infiltration. The bent piece of metal is tensioned so that it's “open” in the winter, when the gap is the widest, and it's “closed” in the summer, when the door presses against the frame. Next: Windows, Doors, Hardware, and Skylights |
