Facts You Should Know About Home Lightning Protection
Everyone knows how devastating a lightning strike can be. Protecting your home from a powerful lightning strike could save your life, the lives of your family members, your home, its' contents and electrical components that keep it up and running. How do you prevent a lightning strike on your home? The answer is..."you can't prevent a lightning strike", but you can certainly nullify or minimize the damaging effects of a lightning strike by having a lightning protection system professionally installed in your home.
Why Am I Talking About Lightning Protection?
I've made another visit to the Victorian Queen Anne that I'm covering and my timing couldn't have been much better. They happened to be installing the lightning protection system and the owner/master installer/designer, Christian Wolf of Wolf Lightning Protection Corp., made himself available to answer a number of my questions. I learned quite a bit and you probably will too if you "read more".
First, I'd like to give you some facts about the system being installed here at the Victorian home.
The core of the lightning protection system itself is the copper cable. Wolf Lightning Protection buys copper cable by the spool. Each spool consists of 250 feet of copper cable that (currently) wholesales at approximately $400+ per spool and rising. The copper cable is made up of 32 wound strands of 14 AWG wire. The Victorian home will use 8 spools of cable or around 2000 linear feet. That's a lot of copper. Christian tells me that he buys around 6000 ft. of copper cable...PER WEEK...so his wholesaler is kept very busy supplying Wolf Lightning with their needs.
There will be several 12" lightning rod spikes installed along the roof ridgeline, including a $400- 20 lb. solid bronze finial measuring in at around 24" that will be attached to the apex of the turret. In addition to the lightning rods, each and every exposed metal vent will have a copper cable attached to it in the interior of the roof (see photos) and there are a couple dozen of them for this house.
The lightning rods are attached by drilling a hole straight up through the rafter and also through (in this case) the Vermont Black slate ridgeline shingles and secured along the interior of the rafter via a brass clamp. The clamp is nailed to the rafters with a copper guide and the cable itself is also secured along the interior of the rafters (and everywhere else) with copper nails to keep it flush against the wood. Are you beginning to sense a theme here? Copper, copper and yet more copper creates a lightning "path" leading straight to the ground should it decide to strike the home. Christian says that you could use aluminum for the system to save money but it's not as good of a conductor as copper and I don't think we want to play with 30 million volts.
The cables run all along the interior of the rafters and work their way down to an exterior cable that is buried no more than 18" underground and surrounds the entire home forming a loop. The Victorian home will require 10 "lead outs" to the grounded loop. I had to ask, "Why no more than 18?" The answer is because the ground that the cable is buried in tends to stay damp within the upper 18" of soil. The damp soil helps to keep the copper cable "wet", thus, becoming a better conductor for the massive amount of electricity from the lightning bolt to follow.
Do homeowners really benefit from a properly installed lightning protection system?
In 2002-2005, only 16% of reported lightning fires occurred in homes but these accounted for nearly all the associated civilian deaths, 90% of the associated injuries, and 58% of the direct property damage.
- During 2002-2005,
What follows is a Q & A on lightning protection that I grabbed from the Wolf website to let you decide for yourself whether or not it's worth it to have it installed, the benefits, how it's installed and more.
I asked Christian if professionally installed lightning protection is expensive? That depends on your perspective. How does an average of 1.5 - 2% of the cost of your home sound? Not so bad now does it?
So now you might be asking yourself, "How much did the lightning protection system cost for this huge Victorian Queen Anne home?"
The answer is around $12K.
Now for the grab...
Q: Do lightning protection systems work?
A: Yes! A correctly designed and installed lightning protection system is proven to completely protect structures from lightning damages.Q: Do lightning rods attract lightning?
A: Definitely not! Lightning rods do not attract or prevent lightning strikes. A lightning protection system simply intercepts a lightning strike and provides a path into the ground to harmlessly discharge the dangerous electricity.Q: Our antenna is grounded, doesn't that protect us?
A: No. An antenna is not designed to handle a lightning strike and, instead, allows dangerous current to enter the home.Q: Do nearby trees protect structures from lightning?
A: No. Many times after trees are struck, the lightning side flashes to the house. Valuable trees can be protected and are often made part of the lightning protection system.Q: Our home is grounded, doesn't that protect us?
A: No. A house may be grounded to assure electrical safety, however, grounding is not intended to prevent lightning damages.Q: Can't we install our own lightning protection system?
A: No. An improperly installed system may be dangerous. Lightning protection is a very specialized industry requiring trained technicians. A proper system takes into account your home's design, construction, electrical components, soil condition, location and more.Q: Won't it ruin the aesthetics of our home?
A: No. The system can be concealed within the walls during construction stage. For existing homes, conductors can be semi-concealed. Modern lightning protection systems are inconspicuous and virtually undetectable.Q: Can surge arresters, suppressors and "whole-house protectors" protect my home?
A: No. Surge suppressors are important components of a complete system, but can do nothing to protect a structure against direct lightning strikes. Arresters must be installed in conjunction with a lightning protection system to provide whole house protection.Q: Do lightning protection systems require routine maintenance?
A: No. Lightning protection systems are constructed of durable materials that are likely to outlast most other fixtures on your home. No maintenance is required unless changes are made to your structure or roof.Q: Is lightning protection expensive?
A: No. Compared to the majority of home improvements, lightning protection is one of the least expensive. It offers the best type of insurance--peace of mind and proven protection for your family, home and valuables. It is a big return on a small investment.Q: Am I safe if my home is in a low lying area?
A: No. Lightning frequently strikes in low areas as well as in higher elevations.
As a matter of interest...
Christian and I discussed his portfolio a bit and I found out that he has traveled throughout the world installing lightning protection systems for some very interesting clients. Clients include (here goes the shameless name-dropping) MLB players Tom Glavine, John Smoltz, Andrew Jones; PGA pro Davis Love III (golfers have a high respect for lightning); some Bonner Custom Homes clients and some others he mentioned that escape me at the moment but will certainly come to me later...not that it matters.
Related:
National Fire Protection Association
Underwriters Laboratory (UL) on Lightning Protection
Lightning Protection Institute (LPI)
Locate a LPI certified lightning protection system installer near you
Surely you're interested in reading more about this spectacular Victorian Queen Anne home.
I've noticed a serious defect in one of the pictures - LPS wire mounted too close to the other wiring. Strike can jump over this cable and completely damage it and of course and devices connected with this installation. If it doesn't jump, it will definitely induct big amount of energy in this wire that will damage devices too.
I also don't think positively about this way of making LPS. European rules completely restrict installing LPS wiring inside of the building (inside of the wall). It can be done this way, but only if the wire has an HV (High Voltage) insulation, but it's very expensive one.
LPS is designed not to lead the lightning strike inside the building, it has to lead it safely outside directly to the ground.
More than one wire connecting ground rods with the roof part is much better than only one. Electromagnetic field will decrease then and the risk of fire will get lower. And the wires can be thinner.
Let me tell you a little story...
Four years ago I was getting ready for bed on a stormy night. As usual when there are storms I unplugged my home theater system, including the coax coming from the satellite dish into the satellite receiver. I unplugged my three computers and their ethernet cables as well as my DSL modem and router including the phone line. Of the items I mentioned none were attached by any means to any outlet, plug, socket, cable, etc. All is good in electronics land.
Off to bed I go up the stairs when BOOM and the entire room turns blue from the flash outside. Feeling my safety I go upstairs to bed.
I wake the next morning to find a pine tree in my back yard split in half from a lightning hit.
That evening as I am cooking dinner my wife decides to play a CD. Turning on the AV receiver nothing more than a loud buzz emits from the speakers. Remembering what occured the night before I check other devices. I lost my Onkyo AV Receiver, a ethernet switch and two pieces of RAM in two seperate computers. All of the devices were unplugged from electrical sockets.
As you say, NOTHING will stop lighting. You can minimize the damage but unplugging won't even do that in some cases.
At our new home I have installed a whole-house surge suppressor. I have battery backups and a separate suppressor with noise filter for my home theater, computers and other electronics. I still unplug everything when not in use out of fear of spikes as well as the green-effort. I do realize now that lightning can still get me.