Adding a space onto an existing house is probably the most cost effective way to increase a building's functional interior space. In this post, an addition suggests what an associate calls a "3 sided" addition. This phrase means to avoid confusion with other sorts of home additions such as raising a structure to develop a new ground level area, or raising the roof to produce a story in between a ground level space and a roof location. The three sided addition indicates that the new and existing structure will share an interior wall.
The first factor to consider when planning an addition is headroom: the height of a ceiling relative to human proportions. The majority of building codes state minimum ceiling heights, however, as the majority of people prefer ceilings that are at least 8 feet (2. 5 m) high, a properly designed area will probably satisfy or exceed these. Ensuring appropriate headroom is most likely the most challenging aspect of addition design, and is the primary reason to begin preparing an addition from the roof down.
Start your design thinking by trying to picture what you consider an ideal ceiling height for your addition when finished. As discussed, many choose a minimum 8 feet, however a few inches less than this will still work in a pinch. It is essential to start here, due to the fact that your brand-new ceiling will likely be hanging from the roof framing that will, in turn, connect to the existing building. If this framing attaches to an existing structure too low, your ceiling will be too low. Let's take a look at a couple standard roof frame strategies to help clarify.
Gable Dormer: When most kids in the western world draw a house, it will have a gable roof. A gable roof is an upside-down "V." A gable dormer is this same roof shape attached to an existing primary structure at an ideal angle. It will have a peak as does the kids's illustration, and where its roof fulfills the main roof is called a valley. As people have been using gable dormers for centuries, you won't have to look far for an example. The main advantage to a gable dormer when designing an addition is that the addition's ceiling height is identified by how high its peak is relative to the primary building. Generally, the greater the peak, the greater the offered ceiling height.
Just like any structure project, there is apparently no end to benefits and drawbacks, and compromises require be discovered. When using a gable dormer frame for an addition, the compromise is that much of its weight will bear upon the existing or primary roof framing due to the fact that it overlaps this framing. As the primary roof framing was not most likely created to support this extra weight, this primary roof frame will have to be enhanced. Of course, there are a few more in and outs to know about putting a lid on your addition using the gable dormer technique, but in my viewpoint, this technique is the slickest, and in the long term, will provide better looks than the majority of options. Due to the structural boosting, and other framing components needed when using a gable dormer, it will likely cost more, too.
If considering the gable dormer technique, something to keep in mind is that because a substantial addition's roof dormer will cover up a significant part of the existing roof, hold off on re-roofing until the dormer is in location. This will save burying a great deal of new roofing product under the new dormer.
Shed Roof: The shed roof or shed dormer has an unfortunate name, but when artfully constructed, shows a cost effective roof frame for an addition, in addition to an appealing one. Beginning again with that inverted "V," the shed-style addition roof is a flat airplane state the shape of a floor tile or square cracker that fulfills one "leg" of the upside-down "V" somewhere. "Someplace" is the operative word because this flexible addition roof style can, when well supported, be attached anywhere on a structure from the main roof to its outside wall. For now, let's suppose the shed roof attaches at the base of the inverted "V." Ideally, the roof joists your ceiling is hung from will "land" on the outside wall plates where the primary roof frame rests. This makes for easier framing.
However here's the challenging part of utilizing the shed-style. Unlike the gable technique which has its drainage slopes developed into the design, that tile shaped shed roof airplane needs to be slanted down, a minimum of a little bit. How much depends on roofing knowledge and the materials chosen. Utilizing the so-called 1: 12 ratio which i consider minimum, for every single foot the roof extends from the main building, the plane, that tile or cracker, tilts down one inch. The challenging part is that at this ratio, every foot away from the primary building is one less inch of headroom. If the addition roof extends 12 feet (4 m) from the primary structure, an eight-foot-high ceiling ends up being 7 with the loss of an inch every foot. This implies that landing your new addition roof on the existing outside wall frame might not supply enough headroom, even when utilizing the minimum 1: 12 pitch ratio. Try this easy formula utilizing a 2: 12 pitch ratio to see why a minimum slope is often utilized. Losing 2 inches of headroom per foot results in the loss of two feet (60 cm) of headroom over 12 feet.
With headroom in mind, you're probably asking, "Can I raise the ceiling to get more headroom?" Yes, but you will concurrently be determining where your new shed roof aircraft satisfies existing work. If that cracker or tile aircraft lands too far up the inverted "V" of the main roof, it will put weight on existing roof framing not planned to support it. This scenario, similar to gable dormers, will demand some engineering thinking and doing, however in my opinion, will be worth the trouble. Shed roofs just look much better when they link to a primary roof, instead of being hung from an exterior wall under the eave.
Another good way to increase headroom is by lowering the addition's floor elevation. This is more commonly essential with single story structures, but can be a challenge even with a 2nd story addition. The issue is, naturally, that by the time that shed roof is extended far from the building and headroom is lost according to the formula, the ceiling is so low as to be impractical. In this occasion, about the only option offered is to "sink" the addition an action or two down to ensure adequate headroom.
A main advantage of the shed roof is its simplicity. It does not demand advanced woodworking abilities to execute as far as roof framing goes. Rather shed-style addition roofs are challenging because they not only need greater idea about drain and roofing materials, however ask likewise for consideration of how building loads are transferred to their foundations, as these are frequently less obvious than with gable-style additions. A last crucial note about utilizing a very little or "low-slope" roof is not just that a low-slope roof material need to be used, but additional care is needed to make sure the addition's roof membrane works out up and under the primary building's roofing product. In general, the lower the slope, the higher this under-flashing.
As always, it's better when preparing a building project to make errors on paper instead of on the job. This thinking is especially real in additions, where certain components of a strategy are pre-determined by an existing structure that might be expensive to alter considerably. Naturally, it's also real that will generally finds a method, so with a little "top down" thinking of addition roofs and some basic tools, a building's usable interior area can be considerably increased without cutting a constructing down and going back to square one.
For more info about roofing for your home addition contact:
Mountain State Roofing
( 303) 816-3693