Pergola Roof Style
Below are comparative drawings of the 4 different rafter and slat spacing options for pergola roofs:
Open Roof Slats 18”, Rafters 18”: The standard Open Roof is the most popular. It uses 1 3/4" x 1 3/4" roof slats spaced 18" apart on center (or slightly less depending on roof size so as to be equidistant from one another). The rafters below the slats are also spaced 18" on center or slightly less and run perpendicular to the slats. This spacing results in a balance between visibility and shade. You get excellent visibility and more shade from it than you normally would think due to the height of the timbers and because the sun is rarely directly overhead.
Open Roof Slats 12”, Rafters 18”: If you prefer more shade you can increase the amount of roof slats to 12" apart on center or closer. Pricing is higher to cover the added timber involved. The least expensive route to add shading is to add roof slats and leave the rafters at 18 inch spacing. If you want more shading than the 12 inches on center, just contact us or make a note in the comments box when you order.
- Open Roof Slats 6”, Rafters 18”: For greater shade than the 12” slat option.
PLEASE NOTE: The best way to increase shading while retaining maximum visibility and not spending anymore money on extra roof timbers is to orient the rafters north and south. If the rafters are running north and south, the sun has to rise and set over them. This gives you a lot of shade in the mornings and afternoons.
The most popular roof style has always been with the slats and rafters both set at 18 inches on center. Please keep in mind it is easy to underestimate the amount of shade the 18 on center spacing creates. If after installation you realize you prefer extra shade, you can add slats then. We keep your construction details filed, so you can add roof slats anytime to create the on-center spacing that will work best for you. Our design pros can help you calculate how many more slats you'd need based on the spacing you'd like to move to.
The Lattice Roof: Creates the most shade and privacy. It's the most popular and lowest cost option to maximize shading. Rafters are set at 24 inches on center when lattice panels are ordered. Each lattice panel is extra strong to resist snow. They are overbuilt with overlapping 3/8" x 1 3/4" slats that have 1 3/4" x 1 3/4" openings. Lattice panels are re-inforced with 1 3/4" x 1 3/4" framing on all 4 sides. The panels are just a fraction over 22 inches wide. The lattice panels sit atop and flush with the roof supports and span the length of the rafters across to the other roof supports. They are fastened to the roof supports and also to the rafters so that the bottom of the lattice panel frames are flush with the bottom of the rafters. Once installed, when you exclude the lattice framing only 18" of lattice is left exposed to the elements. With the lattice also protected by the roof slats that run every 24 inches on center above them, they can handle snow and wind for many years.
Arched Roof with Lattice Panels: If you prefer both a lot of shade and a stylish arched design, then this popular Pergola roof style is for you. The arched rafters are set 24" on center. The lattice panels are fastened in-between the rafters and sit on the Roof Support timbers on either end of the Pergola. The Arched Design has very tall Roof slats measuring 1 5/8" x 5 3/4" notched above the arched rafterstall roof slats spaced 24" on center above them for addiitional strength and protection
Arched Roof without Lattice Panels: Same beautiful Arched Rafters but with an open roof (no Lattice Panels). The arches are set closer together at 18" on center with the 1 5/8" x 5 3/4" roof slats above also set closer together at 18" on center for addiitional strength and protection. The Arched Roof without the Lattice Panels provides considerable morning and afternoon shade. Because of the taller slats used in the Arched Roof, you receive almost the same amount of shade whether you orient the arches or the slats above them North and South. So, this design gives you the added flexibility of orienting it the way that works best for your spot while still maintaining a maximum of both visibility and shade