About Avalon Log Homes
Avalon Log Homes - Blending Luxury with Nature Avalon Log Homes is your Log Home connection all over the USA & Canada. Our expert team provides the finest quality log products and planning services to make your dream home become a reality. Log Homes, Custom Homes, Custom Design Services,
Avalon Log Homes was founded by industry veterans and seasoned business
Professionals with close to a century of collective experience and more than 1000
log & conventional homes built. While Avalon Log Homes is certainly not the oldest log home manufacturer in the business, or the biggest, we are absolutely committed to becoming one of the world’s premier log home manufacturers.
Since our inception, we've built our business and strong reputation on a few basic
Core Values that guide everything we do. These include Integrity, Pride, Service,
Stewardship and Quality. Operating in this fashion has helped us grow Avalon Log Homes to be one of the fastest growing, most well respected log home
manufactures in the business.
Saturday, October 31, 2009
Weather Considerations not Usually Considered in Log Home Design and Construction
Reblogged from LHOTI
By Kim Elmore, PhD.
Kim Elmore received his B.S., M.S., and PhD. in meteorology from the University of Oklahoma. He has done extensive research at the National Center for Atmospheric Research (NCAR) in Boulder, CO, and worked at NOAA's National Severe Storms Laboratory. See end of article for a better glimpse of our resident PhD.
As a research meteorologist who specializes in severe weather, I thought long and hard about severe weather as we designed our log home. A colleague once put the problems severe weather pose as follows: it’s not the odds, it’s the size of the bet! Most information about how weather affects homes details the problems of making the home weather-tight, insulation properties, heat loads, etc. These items mainly refer to HVAC considerations. But weather is much more than seasonal averages, or even seasonal extremes, such as the 90th percentile of low or high temperatures. My concern here is with severe weather: the stuff that gets your NOAA weather radio beeping, or your local TV meteorologist showing off their radar. Here I’ll discuss mainly wind survival. Note that I’m not a structural engineer: make sure you work with one who understands your concerns.
On 3 May 1999, a complex of tornadic storms traversed Oklahoma and Kansas, killing 49 people and leveling entire neighborhoods. In the Oklahoma City metropolitan area alone, thousands of homes were destroyed. Damage ranged from F3 (roofs and some walls torn off well-constructed houses; trains overturned; most trees in forests uprooted; heavy cars lifted off the ground and thrown) to F5 (strong frame houses leveled off foundations and swept away; automobile-sized missiles fly through the air in excess of 100 meters; trees debarked; incredible phenomena). FEMA commissioned a Building Performance Assessment Report to examine the nature of the damage. Their report is contained online at http://www.fema.gov/library/viewRecord.do?id=1423. At 200 pages, the report is thorough, covering both residential and commercial structures. In this brief write-up, I’ll cover only the highlights of what was learned in making that report and how it might affect your home design.
No log homes were mentioned in the report and I know of none that were in the damage path. However, the historic Tri-Cities tornado of March 18, 1925 did pass over many log homes. Subsequent research showed that these homes typically remained intact, losing only their roofs. All other homes were typically destroyed. Some of these log homes remain intact to this day. Local residents attributed log home survival to their spiked construction and heavy log walls.
What about safe rooms? A safe room is a structure that is built to be independent of the rest of the home. It is your last refuge in the event of a tornado. In most cases, a log wall at least 8” thick is as strong as the wall of a safe room, but the problem of missiles remains: they probably won’t penetrate the walls with any remaining energy, but they will come through the windows and, while not posing a structural issue, they do pose a survival issue. Safe rooms protect the occupants from wind-borne missiles. Without a safe room or storm cellar, you must find someplace in your home where you will be protected well. Yet, your home must also protect you from severe weather short of a strong tornado. This is where proper engineering and careful thought come into play.
In typical frame construction, the walls and roof form an integrated structure. In severe wind storms, the roof is usually separated from the walls, at which point the walls fail and the entire structure collapses. Log homes have self-supporting walls and so will probably remain intact should the roof be separated from the walls. However, there are things that every log home owner should do if they live anyplace where high winds might occur in severe weather (this includes wind storms such as Chinooks and boras). While your home is very unlikely to suffer a tornadic onslaught, it is likely to endure winds of up to 100 mph anywhere that thunderstorms occur. Along the Gulf and southeast coasts, hurricane winds are also a significant threat.
First and foremost: maintain a continuous load path from the roof joists/trusses/rafters all the way to the ground. And make sure that it terminates in something (like a stem wall) that will not be pulled out of the ground. You can accomplish this with hurricane clips, straps, or any number of other methods.
Simply keep in mind that the forces involved will tend to lift the roof, so you must use a method that will not fail under tension.
Nails and screws must not be prone to pull out: these attachment methods are strongest in shear and weakest in tension. One obvious exception to this are the long screws used to build up a log wall in a milled log home: by design, these are quite strong under tensile loads.
Regardless of building codes, the first course of all external log walls should be attached to the stem wall with J-type bolts set in the concrete, though there may be alternative fasteners such as continuous through-bolts. The next course should be attached to the bottom course with screws intended for log applications, and so on. Roof trusses, joists, or rafters must then be attached to the last course of logs such that they will not easily be pulled free. When more than one floor is involved, how the load path is maintained depends on the construction method. In our milled log home, the second floor is attached with large screws and specialized clips to the top course of logs, and all subsequent external framing is attached to this floor using hurricane clips.
Another important consideration is outbuildings: make sure your outbuildings are as wind-resistant as possible. Many structures fail under otherwise survivable winds because of wind-born missiles. Imagine how much damage a few 2x4 studs could do if hurled at 100-150 mph at your house. And in all cases, it’s best to have your home engineered with continuous load paths and wind survivability in mind.
Assuming you have succeeded in building your house with a continuous load path, the next consideration is siting. The most common roof failure mode in and around the Oklahoma City area was overpressure due to garage door collapse. In these cases, the garage door collapsed inward due to strong winds. This created a large opening that was pressurized by the wind. This pressurizes not only the garage but any attached structures and so lifts the roof off of the walls. Large garage doors, such as those used for single-door two-car garages, are particularly vulnerable. In addition to the door itself failing, the rails on which it runs are also subject to failure: these must be reinforced with wind survivability in mind. In our case, we have a detached two-car garage (a failed garage door will result in damage to only the roof of the garage) with two single doors that face north. Single doors have twice the fastening to the structure and are far less likely to buckle.
In most of North America, strong straight-line (non-tornadic) winds will typically have a south-westerly to westerly component. This is because the strongest thunderstorms tend to be associated with south west to west winds aloft and thunderstorms have the ability to bring these winds to the surface. Strong surface winds can occur from other directions (the Santa Ana winds of California are easterly and microburst winds can be from any direction) but the very strongest winds are routinely south westerly and westerly. Hurricanes are the exception: the strongest winds are always in the onshore flow. Along the Gulf coast, these winds will be southerly, but on the East coast they will be easterly.
So, avoid exposing any particularly vulnerable structural components to these winds. Vulnerable components include not only garage doors but also large windows.
A north-facing garage means that any ice accumulation will be slow to melt, because of the low sun angle in winter. A more winter-dominant climate would have to deal with ice and snow buildup on the north side of the garage. Yet, in the southern plains we are nearly assured of seeing 100 mph winds over a 20 yrs period. A slick driveway is far less inconvenient that a destroyed home.
Our home was built in an exposed area, well clear of any trees. However, our previous home (milled yellow pine logs fastened with spikes) was nestled in the trees, on the northeast side of a northwest-southeast ridge. We seldom experienced strong winds there. Trees will indeed lessen the damage wind can do to your home, as long as you are well within the trees. They may fall on your home, but they will also significantly lessen the strength of even tornadic winds and so protect you and your home to some extent.
Keep these ideas in mind as you plan and build your home. If in doubt, contact your local National Weather Service Forecast Office and learn about historical wind damage in your area.
Wednesday, October 28, 2009
Check out our Log Home of the Month- Springdale Plan at http://www.avalonloghomes.com/floor-plans/springdale
To view a video of this home go to http://www.youtube.com/watch?v=6lV7P3Oi8Z8
This Springdale Model is one of our most popular log homes. This plan radiates a warm comfortable feeling through its bright open design. The kitchen, dining & living areas flow together which proves to be functional and elegant. This 3 bedroom 2.5 bath 1-1/2 story with optional basement plan offers all the extra special touches. The family room with a huge full glass prow is enhanced by a stunning fireplace. Inside, the well-integrated main living areas are geared for the views to the back patio, which is the perfect complement to the views beyond.
2280 square feet total.
Saturday, October 3, 2009
Borates for Custom Log Homes
By Greg Steckler
Let’s talk for a bit about borate treatments for your log home or cabin. If you’ve never heard of them, you are probably asking, why would I want it? Well, do you hate the thought of termites of all kinds eating at your house? How about Carpenter ants, Old House Borer beetles, powder beetles, and post beetles? Finally, how about Brown Rot, White Rot, mold, mildew and other wood decaying fungi? I didn’t think so. You know, borates can and do kill all the above insects and organisms. Sound a little more interesting now? Let’s get started.
What is borate? Disodium octaborate tetrahydrate, or DOT, (no not THAT DOT, this one
really works!) is a borate salt compound that is formed from a union of boric acid and borax. This is the most common form of borate used in log home treatments. Various name brands of water based borate solutions are available, such as Armor-Guard, Timbor, Penetreat, Board Guard, and others. There are also several glycol based solutions, such as Bora-Care and Shell Guard. Finally, there are oil based and solid forms of the product, sold as rods that can be inserted into logs in your log home and provide long term protection.
How do borates work? Borates are toxic to both insects and fungus species. One way the borate works is that it disrupts the enzyme system of the insect and destroys the
microflora in the stomach of the insect, thus disallowing food digestion. Borates also affect the enzyme system of fungi. Finally, the active ingredient is a contact toxicant to fungus.
How do I apply it? First of all, it’s important to realize that the borate needs to soak as far into the wood as possible. There can be no stain or other finish on the wood when the borate is applied. The best way to prep for borate is to cob blast the wood, making it even more porous. Every borate manufacturer has different methods of application and a special focus on what their product will do. Let’s look at them as groups, and not brand names.
First, you have your glycol based treatments. These are marketed more for termite and
other very long term applications. Check out www.Nisuscorp.com and
www.permachink.com for more info on each of these. Typically, these are mixed with warm or hot water and spray applied to saturation. The glycol is very good at pulling the active ingredients deep into the wood, where only saturation with water will remove them.
Second, there are water based solutions. You’ll buy these as a powder in some size pail. So many scoops to the gallon, and again, you are spray applying these onto the wood surfaces you want to protect. Protection is good near the surface, about a quarter inch or so. A hard rain will wash it off, which is why you need to coat the wood soon after with a stain/sealer.
Third, there are borate rods. Cobra Rods and Impel Rods are the most popular. These
rods are made for high risk areas of your log cabin, such as log ends that get a lot of
splashing water on them, or protrude out past the overhang. A hole is drilled, the rod inserted, and a plug tapped into place. If the log gets wet, the borate will diffuse into the surrounding wood, protecting it from rot.
Finally, taking into account that many borate treatments are applied specifically for the purpose of protection log homes, which will require a sealing stain treatment anyway to lock in the borate, there are a few companies working on a penetrating oil based application of borate, which will allow other ingredients such as base color pigments to be introduced deep into the wood as a conditioning step, after which a positive curing top coat is applied to “lock in” the borate.
While borate solutions are very good for pretreatments before staining the wood on your house, they only help prevent mold and mildew from forming UNDER the stain layer.
They do NOTHING about mold or mildew on the surface of the stain. Only a periodic
cleaning will remove that mold or mildew, and borate treatments should never be viewed or presented to a consumer by a restoration contractor as a way to avoid regular maintenance.
Originally appeared in the column, The Log Home Corner and reprinted here by
permission from the author, Rich Littlefield.
Rich Littlefield has been in the log home restoration industry for almost a decade. In addition to using almost every commercially available stain in the area, he has developed a stain system that addresses concerns found specifically in the Southeast geographic region. He has given restoration and maintenance seminars at various log home shows and manufacturer sponsored events. He also offers maintenance seminars and plans for Home Owners Associations, commercial complexes, and individuals. Finally he is fully involved in consulting, evaluations, and offering restoration services and supplies.
See this and other articles at http://www.avalonloghomes.com