Heritage Windows: Repair vs. Replacement

Photo Credit: K. Manning

So, you own a home that was built prior to 1940 and you’re listening to all the hype out there from window companies about how great vinyl windows are at saving you money on your heating bills. You want to rip out those old “nasty” windows and put in some vinyl instead. Should you do it? There was a workshop I attended on November 20^th that was sponsored by the Aurora Heritage Advisory Committee that addressed the prevailing attitudes about our society’s need to abandon the old and adopt the new when it comes to replacing windows in older homes. You may save a few dollars in the first few years, but that will eventually change. Quite simply, you could be causing your home more long term damage if you replace those old wood windows with vinyl. An alternative you should consider is repairing your original windows instead. 

This 2 hour workshop was led by Dr. Christopher Cooper, the Editor-in-Chief of Edifice Old Home Magazine, the only magazine in Canada dedicated to the repair of older homes. Chris Cooper has over 25 years experience in the repair of heritage homes and heritage buildings in Canada, the US, Britain and around the world. He is a passionate advocate for “stabilisation” or the repairing, where ever possible, of the character defining elements of your older home. The first part of the discussion explained the R-values of both older wood-framed windows and newer vinyl windows and the results were quite stunning.

Photo Credit: Home Depot Canada, homedepot.ca

An R-value is a measurement used in building construction to determine heat resistance in terms of insulation. You’ve probably seen insulation bundles with numbers like R-14 or R-20 and wondered what they meant. That number doesn’t refer to the thickness of insulation but the resistance of heat flow over the product. Well, windows have those R-values as well but unlike insulation, where a higher number means better insulation, the goal is to get as low an R-value as possible for windows. In terms of storm windows for your older home, a single-glazed window with a wood frame has an R-value of between .44 and .49. A new vinyl, double glazed window has an R-value of between .51 and .55. The spread between these two on first glance may not seem large, but it would be the equivalent of the spread between 4 and 8 on the Richter Scale…so a huge difference in terms of heat loss. Again, the goal is to get that number as low as possible for that determines how much heat loss your windows are producing. So your question right now is probably “How can this be? How can a newer window produce more heat loss? That’s impossible!” It’s a fair thing to ask as home owners have been pressured into believing for many years by groups from house insurance companies, mortgage lenders to window manufacturers themselves, that newer is better. But it makes sense, if you think about it, why newer windows are less efficient and contribute to future rot, mould build up and decay of your home.

Photo Credit: stonehousesofontario.net

It is estimated that one in fourteen buildings that survive today in Canada were built before 1914 and one in seven buildings built prior to 1945. This means there are a lot of “newer” constructed buildings in Canada that were built in the last 70 years. Adding to this further, Dr. Cooper explained that the wood materials used in heritage homes and buildings, including window frames, came from old growth trees prior to 1920. After about 1925, the old growth trees were highly depleted and second growth was starting to come into use. First growth is the best possible wood to use as the trees were very slow growing and had tighter rings. The tighter the rings, the stronger the wood and less vulnerable it will be to insects and general rot. Second growth grows at a much faster rate so, therefore, has much wider rings in the wood grain. Wider rings mean vulnerability to wood loving insects and moisture damage. We are now starting to see third growth forests, or “force-fed” trees specifically designed to grow very quickly and be harvested within a few short years. This type of wood is even more vulnerable to decay through moisture and insect infestations.

Windows were designed specifically to fit the house being built. Over the years, sagging due to the natural effects of gravity occured and if these windows are replaced with vinyl, in effect they will not fit properly and will cause moisture, the outside air, dust, insects and other elements to eventually invade which will cause damage to the home in the long term. The truth is, vinyl does not “breathe” like wood. The Canadian Dept. of Natural Resources Consumer Guide of 2005 states “The disadvantages of vinyl framing material is that vinyl expands and contracts with temperature, opening up cracks for air leakage.” Adding to this, the Canadian Center for Energy Technology, Study of Long Term Performance of Operating Windows in 2007 stated “Air Leakage in vinyl windows increases 136%, significantly more than aluminum or wood. Un-reinforced PVC profiles have a lack of rigidity and a high coefficient of expansion; PVC profiles are subject to distortion.” In their studies, they found that vinyl windows have a tendency to bend, distort, and even crack, especially in regions of Canada that experience cold winter months.

Photo Credit: Vinyl-Windows.org

Photo Credit: Vinyl - Windows.org

There is also the environmental concern of vinyl (PVC) being used in newer windows. Vinyl is a petroleum by-product and the double glazed windows contain argon or krypton gases that are supposed to make them more energy efficient. If your vinyl windows fail, you have released these dangerous gases into the atmosphere. Dr. Cooper told the group that all you need to do is google “windows” and “class-action suit” and you will see all kinds of people banding together in suing the window companies for their windows that have failed. How can you tell if your double glazed vinyl windows have failed? If you see fog like condensation of any kind in the space between the two panes of glass, this means they are no longer doing their job of insulating. You will also experience rot and mold growing inside the ill-fitted frame which is a result of outside air and moisture seeping in. On average, between three and seven years after installing these windows, you will start to see these kinds of effects. At this point, you may want to consider climbing aboard the class-action suit train.  The best way to achieve good results in repairing your original wood windows is to fix up the damaged pieces by using old growth wood in your repairs or a highly effective epoxy to fill in the rotted sections. Okay, so how on earth can you get your wee hands on some old growth wood if the supply was depleted by 1925? It’s not as difficult as you may think. And it doesn’t require mass forestry to make it happen.

Photo Credit: WC Barnes Photography

Photo Credit: Tourism Nova Scotia

There are still a number of old growth forests left in Canada from Clayoquot Sound on Vancouver Island, to Ontario’s Quetico Provincial Park and Pollett’s Cove in Nova Scotia just to name a few. Though logging is highly restricted in many of these forests, it is still necessary to weed out a few trees from time to time to encourage the other trees around to keep growing. There is also the environmental factor such as trees being blown down in windstorms, which is very common in coastal forests.

Photo Credit: Ernie Berry

It is possible to purchase these trees through the forestry companies in that region. As someone who comes from a multi-generational forestry industry family in both Quebec and British Columbia, I knew of people buying up wind felled old growth trees all the time for various furniture or restoration projects, so it is more common that you might think. For one tree, depending upon the size, you can expect to pay $15,000. You can, however, turn around to sell portions of that same tree to carpenters specialising in heritage restoration work for as much as $300,000.  Another way to find old growth wood products, including window products, is through a number of reclaim companies that will go into a demolition site and salvage any products that can be reused in future renovations. But, if you feel you can’t afford to buy old growth wood or reclaim products, you can use the next best thing which is a high grade liquid wood epoxy that can be applied directly to the old wood.Yes, in the very short term, it is cheaper to buy vinyl windows for this reason alone. However, vinyl windows are not designed to last much more than 20-30 years, so be very wary of the so-called “lifetime waranty” attached to the product. It comes with a long list of “exceptions” you may not be aware of at the time of purchase. You will very likely have to replace those vinyl windows….and likely repair the damage to the structure of the house around the window at least once during your tenancy. And that could really cost you. It will also mean that, in general, the house will not live on for consecutive generations to enjoy. With old growth wood windows, you will be able to pass that heritage home down and know it will stand and continue to be appreciated for many generations to come. So now you might be saying “Who cares about the house? I’ll be long gone.” Well, thankfully the folks who built Sinclair Inn at Nova Scotia’s Annapolis Royal didn’t say that.

Photo Credit: Annapolis Heritage Society

Photo Credit: Annapolis Heritage Society

The Sinclair Inn Museum in Annapolis Royal, Nova Scotia is the oldest Acadian home and the second oldest framed house in Canada dating back to about 1720. But it has a unique feature in addition to this. It has the oldest wood framed window in all of Canada that dates back to between 1690 and 1710. How is this possible? It was a recycled window that came from another building.  The bulk of Chris Cooper’s presentation talked about how he and his team restored this national treasure by painstakingly removing the window, removing the glass sections, restoring it fully, then put it back together and reinserted it back into the house. In the pictures below, you can see the damage done through 300 years of gravity and some isolated rot before the restoration began. The green tape you see on the individual panels of glass acted as a guide to Dr. Cooper and his staff in making sure each panel was returned to its original place in the window frame. This restoration work was done this past summer.

Photo Credit: Annapolis Heritage Society

Photo Credit: Annapolis Heritage Society

Dr. Cooper used an epoxy called “liquid wood” which is only available from the US through Abatron, a company specialising in restoration products. The product can be placed directly over the rotted sections and hardens like steel. He said it sets so strong that it is possible to drive a screw through it after 30 days. He also showed us a short video on how he re-puttied the glass and where new wood was used to replace the flags. The flags are the cross pieces inside the individual glass panes. Check out the following pictures to see how this epoxy works once it is sanded down. He also explained the process of good paints to use, the use of linseed oil to refurbish and rejuvenate older wood and where and how often it is necessary to paint a window frame. It is like anything in life, really. If you want to make sure something is well maintained and properly cared for, you have to be willing to put the time and a few dollars into it. If not, then neglect will eventually catch up to anything and it will cost you dearly to repair/replace in the end.

Photo Credit: Annapolis Heritage Society

Photo Credit: Annapolis Heritage Society

This workshop in Aurora was attended by a number of people from municipal heritage planners to carpenters to heritage home owners. Although he did not come out and directly say it, Dr. Cooper alluded to something that I have always advocated when it comes to heritage and history in general: education and solid public relations is the key to understanding issues at hand. For example, six types of PVC (vinyl) double glazed windows have been banned in the UK since 2006 because of their environmental and performance pitfalls. When a seminar such as restoring old wood framed windows is offered in the UK, hundreds turn up and many are turned away at the door because there simply isn’t the room to accommodate them all. I signed up for a similar event in Oxford in 2009 and the event had sold out six months prior and 800 people showed up! But, I think we live in a society where many value the new over the old and if not that, than whatever is cheaper to do. Granted, restoring wood framed windows is not cheap, but if you look at the long term lifespan of that product, then it is a very good deal to restore. If a heritage building is properly maintained, with proper materials, there is no reason why that building cannot survive another 200 years and Canada will one day be able to compete with the major cities of Europe who have passed down their buildings through the centuries.

But education and research is the key to letting people know what their options are. Right now, these highly effective restoration construction materials are only available through suppliers in the US. Chris Cooper hopes to change this by working to become a Canadian distributor of these products fairly soon. He also is working on putting together a television series dedicated to showing you, the heritage home owner, how to restore your windows, floors, plaster ceilings, and how to make your home more energy efficient without the need to change any of your home’s character defining elements. His seminars sell out across the countryand are available on DVD. Edifice Old Home Magazine and its website are a great way for you to pick up a few of Cooper’s tricks of the trade.

If you’re also concerned about costs that may add up for repairing your old windows, don’t fret. In many municipalities across the country there are heritage grants you can apply for to help you make your repairs. Please look at my Links section for a Heritage Advisory Committee in your location. I am still developing this section, so if you don’t see your community listed yet, please consult the planning department where you live and they will guide you. Would you like some more information on how Chris Cooper can help you? Check out the Edifice Old Home Magazine website and send him an email with your restoration questions. If you also want to read more about the Sinclair Inn restoration project, please go to the Annapolis Royal Heritage blog to see the four parts of this project. The four sections were added to the blog in June, July and August of 2010. It is also a great blog to check out the general history and heritage of the Annapolis Royal region. And, finally, for more information about the restoration products used in this window project, please visit the Abatron website for details.

My thanks to the Town of Aurora’s Heritage Advisory Committee for organising this event, to Mai Al Nabhan, Manager of Heritage Planning and Urban Design for the Town of Aurora, and of course to Dr. Christopher Cooper for the fabulous presentation.

Uncategorised adaptive re-use, conservation, restoration, seminars