Structural

Structural Information

Home Structural Issues

Below is a typical wall section. A similar one should be included in every set of blueprints. It will have most of the structural information on it, while the remainder should be on the floor plans, such as steel beam and column sizes, longer than normal headers and lintels, hip and valley rafters and other exceptions.

There may also be some structural information on the elevations and roof plan. Ceiling heights and types, (cathedral, tray or vaulted), should also be on the floor plans and shown in the full building sections.

The list of explanations on the bottom keys to the numbers on the drawing. This is only a guide and you will have to substitute sizes and materials to suit your particular needs and geographical location, but the important thing we stress here is that you provide adequate information on your plans to avoid any misunderstandings, and to thwart any sub contractors that may take advantage of an omission to bill you for an unjustified extra charge.

If you do not use a licensed architect to prepare your plans, as many building departments require, you should at least take whatever plans you have to a structural engineer who can size, detail and specify all of the structural members you will need, even the concrete.

If you buy a set of plans from a magazine etc., it will almost always require modification, especially the foundation, since the person who prepared it has no way of knowing the climate or soil conditions where you live. A licensed engineer's approval of your plans will also satisfy most building departments.

This can be done quite reasonably, and this is not the place to save a few hundred dollars by hoping your home will withstand a wind or snow storm. You should sleep well, knowing that it will!

If you wish to use manufactured floor or roof trusses, as we like to do, the manufacturers engineering department will generally analyze your plans, and determine the truss strength you need, usually at no charge to you if you buy the trusses from them. Most building departments will accept their specifications also.

They may also do the same for headers and ridge beams at cathedral ceilings that they provide. You may still have to engineer any steel beams needed. If possible, consider spanning your entire basement with floor trusses instead. This can eliminate the need for steel beams and any columns that break up the basement.

10" thick by 20" wide concrete footing with a 2" by 2" keyway and 2 #5 continuous steel rods poured a minimum of 6" below the frost line and at least 6" deep into undisturbed soil with a bearing capacity of at least 2,500 lbs. per square foot, . If the bearing capacity is less than specified, the size of the footing will need to be increased accordingly. Your local building department will know the frost line depth for your area.
A 4" perforated drain tile surrounded by 6" of 3/4" stone on the outside perimeter of the footing draining into a sump pit in the basement or other suitable outlet.
A 4" thick concrete slab with fiber mesh , on 6 mil polyethylene vapor barrier, on 4" pea gravel.
10" thick formed concrete foundation wall a minimum of 6" above grade with 2 #5 continuous steel rods at the top and bottom and a 5" wide by 6" deep brick ledge. (8" wall for a frame only building). Damproofing on the exterior of the wall. We do not recommend concrete block foundation walls.
Aluminum drain gutters and downspouts with splash blocks.
2x6 treated sill plate with sill sealer bolted a minimum of every 5 feet with 1/2" by 10" anchor bolts embedded in concrete foundation walls.
Owner selected face brick on the first floor with weep holes at 2 feet on center and fabric wall ties spaced a maximum 24" horizontally and 16" vertically. Maintain a 1" air space between the brick and frame wall.
1/2" underlayment on 3/4" T&G plywood sub floor glued and nailed to 2x10 #2 spf or hem fir floor joists at 16" on center with solid bridging every 8 feet. Building paper between layers to prevent squeaking.
2-1/4" Colonial Pine baseboard and 1/2"x3/4" base shoe trim. Colonial Pine trim on all doors and windows.
1/2" drywall taped, sanded and primed. 2x6 studs at 16" on center for exterior walls, (2x4 studs for interior). R-19 faced batt insulation. 1/2" 5 ply cdx plywood sheathing. Typar or equal house wrap, taped.
Double 2x12 header over all doors and windows unless noted otherwise on floor plans. (1-3/4"x11-7/8" microlams can be substituted for 2x12's).
1/2" drywall ceiling taped, sanded and primed.
Limestone sill under all doors and windows installed in brick walls.
Steel or stone lintels above all doors and windows set in brick walls. See floor plans for sizing.
Cedar lap siding with an 8" exposure on the second floor. Cedar siding to overlap brick by a minimum of 1". 1x6 cedar corner boards.
Metal flashing above all doors and windows.
2x8 #2 spf or hem fir ceiling joists at 16" on center. R-30 faced batt insulation. 1/2" drywall taped, sanded and primed.
2x8 sub fascia. 1x8 cedar fascia. 3/8" cedar soffit with a 2" continuous soffit vent.
Install baffles as required to maintain a minimum 2" air space between insulation and roof sheathing.
Continuous ridge vent. 235# fiberglass shingles. 30# building paper. 1/2" 5 ply cdx plywood sheathing. 2x10 #2 spf or hem fir rafters at 16" on center.
10" concrete foundation wall flared to 16" at the bottom poured into a trench which is a minimum 6" below the frost line and 6" above grade. This type of foundation may be suitable in some areas for single story residences. For 2 story residences, a formed foundation similar to the one shown above, just not as deep, should be used. Check with your building department. If you do not want a basement, this is an economical choice and can be used with a concrete floor instead of the wood floor joist option shown.
2" concrete slush coat on polyethylene moisture barrier on 4" pea gravel. 24" high crawl space between concrete and bottom of floor joists.
Another very economical option in some areas is a 5" thick reinforced concrete slab thickened to at least 12" at the perimeter for at least 24" with continuous #5 steel rods. In this case, heat ducts would be in the ceiling or attic. This is not a good option if a brick or stone building is planned. Use caution and do some research before going this route. With this option plumbing and electrical will be embedded in the concrete floor. If the slab should somehow become cracked, or other piping problems arise, you may have to tear up the concrete for repairs!
This type of foundation is most often used for detached garages and other outbuildings that are not normally heated and may not have much plumbing.

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