Anchor Bolts:

Prefer epoxy anchor bolts to wedge and under cut bolts. Less chance of making a mistake, but the holes do need to be blown out with forced air.

Beams, Girders and Headers:

Should always break on top of the pier or column. No splices between piers or columns.

Girders should be positioned in the middle third of the pier to center the load on the footing. Offsetting the girder on the pier rotates the footing.

Do read all of the notes and study the details

Do not scale the drawing or the details, if the architect or engineer wants you to have a dimension they will provide it.

Architects and engineers try not to provide information (notes, dimensions) more than once, if a change occurs then they have to search for 2, 3, 4 or more locations to change. This is frustrating for the contractor to search for a note that is in only one location, or worse – the note has been left off.

Architects and engineers try not to duplicate their efforts, the main concern is that a dimension or note is different. When reviewing the plans the information that you are searching for in the structural drawings may be on the architectural drawings only.

Brick is considered to be a brittle material and can crack with very little deflection. Brick lintels, over windows and doors, are typically steel angle shapes to provide strength and a seat for the brick to bear on. However, steel angles are not stable. Steel angles need to be secured (fixed) by the brick veneer. Brick lintels require a MINIMUM bearing length of 8 inches into the brick to stop the angle from twisting.

Inspections of residential and commercial brick work typically yield bearing lengths of less than 1 inch.

Typical residential construction consists of a masonry wall with a brick veneer. The structural load of the residence is placed solely on the masonry wall. However, sometimes the masonry wall is only 4” wide and the sill plate bears on both the masonry block and the brick, thereby making the brick part of the structure and not just a veneer. This condition can vary around the perimeter of the residence.

When the brick work is flat and exposed to the weather, water penetrates the mortar joints and begins to break up the mortar joints over a few years.

Conspec Weather Seal WB can be applied to the brick and mortar to provide protection. The Sioxane Penterating Sealer does not produce a shiny finish. However, try a small application in an inconspicuous location to determine if the cosmetic features meet the approval of the owner.

Building Codes are designed to provide minimum design requirements. These requirements are there to ensure that a builder does not build something shabby or too small to live in. Designing to the minimum building code requirements for a 3,000 sq ft ($300,000 and up) houses will result in a structure that the homeowner will not satisfied with. Many of our home builder clients build above the building code requirements.

Not required by Residential Building Code, however do not contract to build a house without it. Prevent moisture damage to studs and sheetrock. Protects against inadequate flashing and poor siding installation. Should always be installed behind a brick veneer.

The N.C. building code used to specify that the chimney footing have a 0” projection to the face of the brick. Over the years the projection grew to 3 inches, then 6 and finally 12 inches. Under the International Building Code, N.C. has stuck with the 12 inch projection. However, new house designs for larger houses have chimneys that are 35 to 45 feet tall with large stone faces on the inside. The footings for these chimneys require engineering design.

The vertical distance a floor joist moves when dead and live loads are applied.

N.C. RESIDENTIAL CODE BOOK DEFLECTION CRITERIA:

Floor joists less than 20 feet long: L/360
Floor joists more than 20 feet long: L/480

Example:

• L/360 for a 18 foot long floor joists
• L represents the clear span distance therefore 18 feet x 12 inches per ft = 216 216/360 = 0.60 inches. this is the allowable deflection when the live load is applied
• L/480 for a 20 foot long floor joists
• (20x12)/480 = 0.5 inches

Engineered lumber is called numerous names, Timberstrand, Microlam (LVL) and Paralllam. Each of these types of engineered lumber are created through different processes. However, the cost of production varies while the overall strength is similar.

Engineered lumber is typically slightly stronger than Select Structural grades of SYP, HF, and DF. The big advantage is that engineered lumber can be obtained in depths of 14”, 16” and 18 inches. Engineered lumber is manufacturer in 1 ¾ inch widths, so that when two pieces are put together they are 3 ½ inches wide – the depth of a 2x4 wall.

Only Microlam (LVL) can be pressure treated. To obtain pressure treated lumber a special order has to be placed. The Microlam has to be produced without Yellow Popular in the process. Yellow Popular can not be pressure treated.

If the weather is very cold, less than 32 degrees F, a fireplace chimney can experience thermal shock gradients between the inside and outside surfaces of several hundred degrees. This thermal shock can crack the brick chimney. Both wood and gas fires can cause this to occur, although it is much easier with a gas log fireplace. On cold nights, start the fire small and slow, gradual increase the heat over a 30 minute period to allow the brick to heat up gradually.

Note #1: Wood floor trusses and wood I-joists can be installed 24 inches on center. However, even using ¾” T&G plywood or OSB, the floor sheathing may deflect slightly so that cracking of marble and granite may occur. Also, with vinyl you may be able to see and feel the location of each of these floor joists. These are not considered structural issues but cosmetic issues.

The bottom of a concrete footing must be placed below the frost line. In eastern N.C. the frost line is 12 inches. Code requires a minimum of 8" thick.

Should be kept open year round. Air needs to flow underneath a crawl space to keep moisture levels below 19% for wood framing. Also limits mold growth.

Rafters – calculate loads based on horizontal distance, use projected loads for slopes greater than 5/12 do not birdsmouth cut the rafter more than 1 1/2”, brace, allow for insulation requirements if rafter spans across kneewall then check floor joist for point load from kneewall. Rafters should be installed directly opposing one another.

Ridge Plate – calculate to span up to dead load of ridge plate, I have seen ridge plates in old houses that are butted together but do not do this. Should be one size larger than rafters.

Ridge Beam – treat as a normal beam with a distributed load on it, check for column requirements and bearing below columns

Valley Beam – calculate as a beam, add rafter jacks to reduce deflection

Hip Plate – acts like a ridge plate, calculate dead load only

Collar Tie – (also known as Wind Beam) a 2x4 or better connection between rafters, located beneath ridge plate or beam

Rafter Jack – 2x4 vertical with 2x6 supported by a 2x4/2x8 beam that spans across a minimum of 5 ceiling joists.

Hip Jack – same as rafter jack, but located beneath a hip

Ceiling Joists – allow for insulation IF placing plywood in the ceiling, typically designed for DL +attic LL

Floor Joists - spans from wall to wall/beam. Supports floor loads. Can be 2x Solid Lumber, Engineered Wood I-Joists (with plywood web), metal plate connected wood floor truss and Open Joist 2000 (glue connected wood trusses).

Flush Girder/Header/Beam - the girder is flush with the top surface of the floor joists. Floor joists are connected with joist hangers to the side of the girder.

Dropped Girder/Header/Beam - the girder is below the floor joists. Example - header over a door in a load bearing wall.

Band Board or Rim Board - outside band around house perimeter - typically 1 ply.

Ledger - a 2x2 wood strip nailed to a girder truss or a girder to support floor joists or ceiling joists.

Cantilever - where the floor joists or trusses bear on the exterior wall and extend out beyond the wall. Floors are limited to 2 to 4 feet. Roof cantilevers sometimes extend out 10 feet.

Frost Line/Footings - In NC, the Code Book requires that footing.

Roof Eave - at edge of roof - where gutter would be placed. Under the eave is the soffitt.

Roof Rake - on a gable end where roof hangs out 12".

Roof Sub-Fascia - at eave of roof - a trim piece.

Roof Ventilation - can be a ridge, gable end loaver or soffit vents.

Band Board (Rim Board) – runs along the ends of the floor joists, provides support to the bottom plate of the exterior walls. Do not use a I-joist for a band board, the plywood soaks up any moisture nearby.

Sill Plate – treated wood that bears on the masonry foundation wall.

Bottom Plate – the wood plate on the plywood floor sheathing, studs bear on the bottom plate.

Top Plate – double 2x wood plates on top of the wall studs. Splices are over lapped by 4 feet. Ceiling joists and floor joists bear on the top plate.

Stone products are brittle and require more support than carpet or vinyl floor coverings. The Brick Association require that stone/brick products be supported to limit deflection to LL/600 criteria or a maximum of 0.3 inches.

Soil in NC is sandy/clay mix and provides very low bearing capacities for structures. Rain water from roofs and moving water through the soil can further degrade the soil bearing capacity.

Recommend gutters, downspouts and drain lines to direct the water away from the foundation and footings.
Recommend Leaf Guard gutter system, I had these installed in 2000 and have not had to clean them. Recommend 4” x 6” down spouts.

Manufacture’s Associations require ¾” thick T&G sub-floor to adequately support the hardwood floors and the thin veneers. Hardwood floor material should be brought into the home for several weeks to adjust to the humidity of the house. This prevents shrinkage of the wood and reduces the chances of cracks and gaps.

Hardwood floors should be nailed per the manufacturer’s specifications, which are typically 12” o.c. Floor are rarely installed with sufficient nails.

Hardwood flooring planks should be run perpendicular to the floor joists, even with the ¾” sub-floor. If not, then the joists will show through the planks, the planks will separate.

The property should be landscaped to prevent water from ponding near the foundation walls and to prevent water from flowing near or through the foundation.

Example is a floor system:
Dead load refers to plywood floor sheathing, floor joists, carpeting, tile, and insulation.

Live load refers to furniture (couches, tables, chairs, water beds – something that can be easily moved), people, box of papers, a computer, a TV, etc.

Species: There are four common species of lumber used in construction: Southern Yellow Pine (SYP or SP), Spruce Pine Fir (SPF), Hem Fir (HF) and Douglas Fir (DF). SYP, HF and DF are similar in strength characteristics. SPF is somewhere between 40-60% as strong as the other three species. SPF is lighter to carry. SYP can be Pressure Treated, SPF can not be Pressure Treated.

Grades:
Lumber can be graded either visually or mechanically.
Strength of the lumber increases as the knots get smaller, tighter and few per lineal foot of board.
Lumber is grade Stud grade, #3, #2, #2Dense, #1, #1 Dense and Select Structural (depending on species) #1 is stronger than #2, #2 is stronger than #3. Select Structural is the strongest.
The stronger the lumber the more expensive the lumber becomes.
In the old days, most of the lumber was Select Structural or #1. Typically, lumber available for home construction is #3 or #2. Wood truss companies and treaters purchase some #1 and Select Structural grades.

There are three types of nailing, Face, Toe and End nailing. To understand the differences in strength of these three types of nails, assume that Face nailing are 100% , then Toe nails would be 67% of Face nail strength. End nailing is approximately 0% of the strength of a Face nail. The failure occurs in the wood – not the nail.

Provide changes in a written form. Keep notes at meetings of changes

The more complete the plans are at the time of permit the cheaper the house. Change orders are very costly for the General Contractor to perform, the effects of the change have to be thought out through the completion of the building.

The homeowner has the responsibility of maintenance of the house. This includes observing the condition of the house after severe weather. Home owners should consider taking photographs of their house before or after a storm to be able to determine the condition of the house. Photos taken prior to a storm help determine the amount of damage inflicted by the storm.

Homeowners should also be observant of water around the foundation of the residence. Water and moisture in the basement and crawl space should be noted.

Partition walls are non-load bearing walls that are located in line (parallel) with the floor joist/truss system. Numerous time we have found that only one joist or truss was placed beneath the wall. On other occasions lateral blocking between two joists was installed. Engineering calculation indicate that an additional floor joist or truss is required to carry the weight of the partition wall, which weighs 10 lbs per sq ft, therefore a 8 foot tall wall weighs 80 lbs per lineal foot. In open foyers, the joists should be tripled to support the weight of the two walls.

According to the American Plywood Association there are no engineering differences between plywood (CDX) and OSB, for ANY consideration.

Advantek plywood contains a sealant that prevents moisture absorption. On large projects in which the plywood can be exposed to weather for more than 7 days, Advantek eliminates the need to remove and install warped plywood.

Products are very specialized and have detailed instructions regarding their handling, usage and installation. Read all of the instructions carefully. Also check out the websites for illustrations and use – applications.

Adhesives – were installed while cold (less than 40 deg), the adhesive never cured, the floor creaked all the time and created trip hazards. Installer left the adhesive out in the truck at night.

Wood I-Joist – sprinkler installer drilled holes through the I joists, destroying 15 floor joists that had to be repaired. Web site had an installers guide to show where to drill holes without destroying the joists.

Wood Floors – have meet architects and contractors who think hardwood floor planks can be installed parallel to the floor joists. Have seen contractors install hardwood floors without allowing 2-3 weeks for the flooring to acclimate to the humidity level of the house, then expanding and bucking after the installation.

This is a partial list to show examples that product installation guides should be read very carefully.

Recommend 30# felt over 15# felt for safety and wind protection. 15# felt can rip under the weight of a worker. Recommend one layer of 30# felt over two layers of 15# felt.

When using roof trusses, 15/32” APA Rated Plywood (½”) is structurally adequate for live and snow loads of Eastern North Carolina. However, with roof trusses spaced 24” o.c. sheathed with ½” plywood, the trusses will show through. Recommend 5/8” plywood with roof trusses. Contractor should be held harmless for “waves” in the roof.

The roof sheathing should be installed with “H” clips to properly space the plywood sheets. The gap created by the “H” clip allows for the expansion and contraction of the wood during the change of seasons.

Roof truss bracing should be installed per the Truss Plate Institute’s HIB-91 “Commentary and Recommendations for Handling Installing and Bracing Metal Plate Connected Roof Trusses”

Typically scissor trusses are installed without a slotted connection to the wall. As the plywood and sheetrock are added to the scissor truss, vertical and horizontal deflection occur. If there are no slotted fasteners on the exterior walls, the scissor truss pushes over the walls.

Initial settlement:

• assuming that the soil is dry during the pouring of the concrete footing, initial settlement of the footing is from compaction of the soil.
• initial settlement can occur in localized areas around the house where large structural point loads occur.

• constant rain water near a footing can degrade the ability of the soil to support structural loads.
• water from downspouts, A/C condensate lines and neighboring properties need to be directed away from the footings

• cracks in brick veneer can be caused by minor settlement of the concrete footing. sometimes these are structural cracks and sometimes they are cosmetic cracks.

Recommend getting an engineer to determine the actual cause of the problem. Use the Engineer’s sketches as part of your contract. (See Construction Sequence on Navigation Bar). A few Contractors have been know to try to change the Engineer’s repair concept to increase the scope and cost of the repair contract. Always get 3 bids from licensed contractors. Have a third party inspect the contractors work prior to payment, either a Building Code Official, another contractor or the engineer who designed the repair.

Do not store wood in the crawl space on the ground. Also, do not landscape with wood chips in the flower beds, as it will attract termites.

Prefer through bolts with washers on both ends. Avoid lag screws whenever possible.

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