How does it work?
Does it work on any kind of roof?
Is RafterEye capable of reading through insulated roof decks?
How does penetrationless rafter center location avoid structural damage?
And cosmetic damage?
Does RafterEye use electrical energy?
What applications does RafterEye have outside of rooftop rafter center location?
What rafter dimensions does the clamp accommodate?
Will it work on log rafters?
Is RafterEye’s technology patented?
Where can RafterEye be purchased?
Is Clampster another name for the RafterEye Rafter Center Locator?
How does it work?
The clamp and Magnet Block assembly forms a magnetic field around and through a roof’s structural member (rafter, truss, TJI, etc.) that can be read with a reading device from the rooftop, directly indicating the center of the structural member.
Does it work on any kind of roof?
The Rafter Center Locator works on any non-steel roof whose structural members are exposed or accessible. Steel roofs block its magnetic field.
Is RafterEye capable of reading through insulated roof decks?
The magnetic field of the Rafter Center Locator has been read through over nine inches of substrate, but accuracy begins to diminish typically at distances greater than about seven inches.
How does penetrationless rafter center location avoid structural damage?
It does so in several ways.
First, the traditional method of drilling probing holes weakens the rafter by removing bulk from the top of the rafter. The resulting voids allow compression stresses to cause greater downward flexion of the rafter under dead, live and snow loads precisely at the location where the attached hardware will concentrate those loads.
Second, as all rooftop installers are aware, it is not uncommon, even after painstaking probing or using other methods of rafter center location, to have a lag screw split a rafter and/or exit through the side due to being even just slightly off center.
Finally, while the attachment hole will be both caulked and filled by a lag screw, each probing hole is a potential route for water leakage. How reliable is the seal below the top layer of roof membrane? Any leak, detected or undetected, is likely to eventually result in structural damage. Given the 20-40 year lifetime of solar and other rooftop installations, it’s a risk that should not be discounted. Accurate centering and minimizing the use of probing holes mitigates these serious threats to a roof’s structural integrity.
And cosmetic damage?
Rafters that are exposed, whether indoors or out, present a special challenge to rooftop installations. Accurate center location with traditional methods almost requires creating at least one visible hole through the roof. Lag screw “blowouts” through the sides of rafters can actually become more common due to guesswork following efforts to avoid leaving visible probing holes. Even after these lags are removed and relocated, scars remain, whether in a porch roof or above a living room. Beyond these forms of cosmetic damage, expanding foam or caulk-type sealants used to fill holes resulting from probing, measurement reference drilling, blowouts, or above-deck insulation removal, can fall onto and damage or ruin antique collectibles, artwork, musical instruments, furniture, carpeting and other finished surfaces located underneath attachment points.
Does RafterEye use electrical energy?
No. The RE1 requires no battery and no household current to operate.
What applications does RafterEye have outside of rooftop rafter center location?
The RafterEye Rafter Center Locator can be used to identify a location through other non-steel surfaces such as floors or walls, as long as there is something to clamp to, or a person to hold the magnet blocks on the other side.
What rafter dimensions does the clamp accommodate?
When fitted with the two Magnet Blocks, the clamp’s maximum jaw opening at which effective clamping is consistently achievable is 7.25″. As rafter width increases, the maximum depth of reach diminishes slightly as follows:
| Member width (in.) | Approx. depth of reach |
| 1.5 | 11 |
| 4.5 | 10.75 |
| 5.25 | 10.25 |
| 7.25 | 8 |
A good reading, however, does not require the magnet blocks to reach all the way to the bottom of the roof deck. It is often enough that they are parallel to each other, and close to and equidistant from the bottom of the roof deck.
For oversize or irregular members, center can be found by two workers. One removes the magnet blocks from the clamp and holds them symmetrically against the roof deck on either side of the member while the other reads the field from rooftop.
Will it work on log rafters?
The RafterEye Rafter Center Locator can be used to locate the “center” (deck contact point) of a log rafter. Because most logs are too large to accommodate the clamp, the Magnet blocks are manually held against the top of the log on both sides. A second person reading from the roof can then locate center normally.
Is RafterEye’s technology patented?
The primary operative features of the RafterEye Rafter Center Locator are patented through the United States Patent and Trademark Office.
Where can RafterEye be purchased?
The RafterEye Rafter Center Locator is available at this time exclusively through raftereye.com.
Is “Clampster ” another name for RafterEye Rafter Center Locator?
“Clampster” was a working name for the RE1 Rafter Center Locator that appeared in some publications.