Mounting Options for Solar Collectors
There are many mounting options for solar collectors, this may include ground mount, roof mount and wall mount. Some important factors in deciding how to mount the solar collectors are:
- the distance to the solar pump station
- the esthetic (looks) of the solar installation
- the safety and protection from damage and vandalism
- clear view to the sky
- ease of access to the collectors and ease of the installation of the collectors
Ground Mounting Option for Solar Collectors
Ground mount is ideal for any solar install as it allows you to minimize your vertical run which can save on installation costs. The other advantage is in ease of service and assembly. When ground mounting, you can also select a more optimal azimuth. In winter you can easily remove snow without climbing on the roof.
The frame system for the ground mount consists of a series of aluminum channels that support the collectors with a wide range of inclination being possible. With a ground mount, you need to ensure that the feet on the bottom of the frame are securely fastened to an anchoring system. This can utilize, for example, heavy building blocks that form the base with concrete lag bolts to fasten the legs to the blocks.
Ground mounted collectors should be protected from children and vandalism; a small fencing system may be installed to protect your collectors especially if you have a larger quantity.
Flat Roof Mounting Options for Solar Collectors
The same frame system is used to mount collectors on a flat roof as is a ground mount, and again a wide range of inclinations are possible. Two methods are generally used to secure the solar panel’s frame to a flat roof. One method involves bolts and techniques that prevent water from penetrating the roof around the bolt holes. Contact a roofing company prior to penetrating a flat roof as leakage can occur.
The 2nd method uses weights to hold the frame secure without penetrating the roof’s surface. The Appendix contains information about how much eight is required under high wind conditions. The wind is the determining factor in calculations weights needed based on the panels angle of inclination and wind speed.
The table below gives the results for various angles, but at the same wind speed of 70 mph.
Weight per foot Required to Stop Pivoting
Pitched Roof Mount
Roof mount is a great way to clear low lying obstacles such as neighbor’s houses and trees. Roof mount usually has the highest chance for unobstructed views. Special care must be taken when installing roof mounts to avoid leaks and ensure there is a solid connection to the roof rafter/truss system.
It is common to see solar collectors installed at the same inclination as the roof. However common roof pitches such as a 1:3 pitch (also known as 4/12 pitch) or 1:4 pitch (also known as 3/12 pitch) are quite shallow and are far from ideal. Some additional inclination should be considered. Roof mount is a great way to protect the collectors from accidental damage such as kids playing baseball, etc…
In snowy climates it may also be necessary to lift the base of the frame off the roof by 6-8” which helps reduce the chance of snow build.
Before you take the time and energy to mount the solar collectors on the roof, be sure to consider the roof’s current condition. If the shingles are curling and show signs of aging, then you may want to put new shingles on before you install your collectors. Also ensure the plywood below the wood feels solid. Look under the attic and inspect for any possible deterioration on the roof sheeting that may need to be replaced 1st. Remember the solar collectors have a life of 20-30 years so you need to ensure this matches the life of the roof itself as removing the collectors after the fact can be difficult and time consuming.
The Sunrain TZ58-1800 30R solar collector has a gross weight full of 114 Kg (250 lbs). This weight is spread over 6 connection or load points on a roof. Most roofs should have no problem handling the load as it is much less than an average person standing on a roof. However if the roof is sagging or feels week, you should call a roofing expert to ensure the roof can handle the load.
Wall mount is ideal if you are trying to do winter solar home heating. The vertical angle provides great performance in the winter and you obtain the added benefit of diffused light reflecting from snow. The steep angle also minimizes any snow load problems.
By creating a steep angle for the winter sun, you will naturally create a poor angle for the summer. This is a great strategy to reduce unwanted heat in the summer.
As with roof mount, you need to ensure the solar collector it is properly secured. This best appearance is if the frame is attached directly to the wall. However some situations may arise where horizontal 2x4 boards are first attached to the wall and ensuring these screws penetrate into the studs, not just the sheathing. Normally studs are 24 or 16 inches on center so, once you find one stud, it is easy to determine where the others are.