Table of Contents
How many rafter ties do I need?
Rafter ties amount to an additional framing member that runs above the ceiling joists and that connects opposing rafters. They are generally required every 4 ft., which means that you need a rafter tie only for every other pair of 24-in. o. c. rafters or for every third pair of 16-in. o. c. rafters.
Do hurricane ties go inside or outside?
What is this? This tie can be installed on the inside or outside of the wall. Keep in mind that these ties create a strong connection between the top plate and rafter, so you may need an additional tie to reinforce the connection between the top plate and the wall joists.
How do you install collar ties in the attic?
Does every rafter need a tie?
Rafter ties are always required unless the roof has a structural (self-supporting) ridge, or is built using engineered trusses. A lack of rafter ties is a serious structural issue in a conventionally framed roof. In most homes, the ceiling joists also serve as the rafter ties.
Can you move rafter ties up?
Figure R802. 4.5 of the 2018 IRC states that a rafter tie can be raised a maximum distance of “HC” above the top of rafter support walls. For example, in a roof structure where the ridge height is 9 feet above the top of the support walls, the maximum height that a rafter tie can be raised is 3 feet (3/9 = 1/3).
Can you use screws with hurricane ties?
Why not use screws? However, the risk if construction screws are used in steel connectors such as hurricane tie-downs is that such screws might break under load across the screw diameter even though their screw design resists pulling out of the wood.
What size screws rafter ties?
5A Hurricane Ties connects the double top plate to the rafter or truss. This clip accepts 8d . 131″ x 1-1/2″ joist nails or longer. You can also substitute the Simpson SD #9 x 1-1/2″ Structural Screw.
What kind of nails do you use for hurricane ties?
While many hurricane ties have been evaluated with 8d x 1½” nails for compatibility with nominal 2x roof framing, some require the use of a longer, 8d common (2½” long) nail and others require a larger-diameter 10d nail.
Does a hip roof need rafter ties?
Rafters span from wall to hip beam or wall to ridge beam. All rafters have a vertical reaction at each end (no horizontal) so no rafter ties are needed.
Do collar ties reduce rafter spans?
Collare ties placed in the upper 1/3 of a roof( by themselves) will do little to stop wal thrust / rafter sag/ or decrease rafter span.
Do you need rafter ties and collar ties?
Collar ties are necessary to prevent separation of the roof at the ridge due to wind uplift. Rafter ties resist the forces caused by gravity loads that would otherwise cause the roof to pancake and push out the sidewalls.
What can I use instead of collar ties?
Cables. Steel cables are often substituted for lumber collar ties. The cables typically connect to framing materials via specialized hooks, brackets or turnbuckles. Depending on your project’s design, the cables can span between the bottoms of rafters, like ceiling joists, or near the roof’s peak, like collar beams.
Where do you put collar ties?
Collar ties attach between every other pair of opposing rafters at the upper third of the roof below the ridge or peak of a roof section.
Are collar ties necessary?
The most common reason for installing collar ties is to prevent rafters from spreading apart under load. However, in a conventionally framed peaked roof, like the kind you describe, collar ties would probably serve little or no function, since the attic floor joists serve as ties to prevent the rafters from spreading.
What kind of nails do you use for strapping?
10d nails are appropriate for ceiling strapping. You can use two nails at every intersection between a joist and the strapping.
How many nails do you need for a hurricane tie?
The Simpson Strong-Tie H3 Clip is part of the Hurricane Tie System that features various configurations of wind and seismic ties for trusses and rafters. A typical H3 installation ties the single top plate to the rafter or truss. The Simpson H3 requires (8) 8d joist nails.
How many nails are in a rafter tie?
As you can see, even at the plate, 15 nails are required for each connection in your 4/12 roof; move the rafter ties up and you’ll need 22 nails per connection.
What is the cut on the rafter that sits on the top of the wall?
What is a Birdsmouth joint or Cut? The Birdsmouth Joint (also called the birds beak cut or birds beak joint) is a small triangular shaped cut out at the base of a roofing joist that allows the joist to sit nicely on top of the wall plate (top of the wall before the roof starts).
Are nails stronger than screws?
When deciding between nails and screws, keep in mind that nails are less brittle, so they provide greater shear strength. Screws, on the other hand, may not be as forgiving, but their threaded shafts hold better in wood and draw boards together much more tightly and they have greater tensile strength.
Can joist hangers be screwed?
joist hanger nails for nailing into the side of the joist (Photo 5); for double hangers, use 8d or 10d nails. For double shear single hangers (Photo 4), fasten the hanger to the joist(s) with longer 8d or 10d nails. The manufacturers agree: Never use galvanized deck screws or drywall screws to install joist hangers.
Are screws or nails better for framing?
Nails are often preferred for structural joining, including framing walls, because they are more flexible under pressure, whereas screws can snap. Brad and finishing nails are great for detail work like securing molding, door jambs, and baseboards.
