<![CDATA[Grist - Comment Feed for Umbra on inefficient windows]]> Grist Comment Feed en Comment #1 by Kathy Austin http://www.grist.org/article/inefficient_windows/ Wed, 08 Nov 2006 05:53:01 -0800 http://www.grist.org/article/inefficient_windows/1 Cold Windows

I too live in a realtively mild CA climate and own a very old home. It took me several years to have enough money to replace the large original plate glass windows in my living room. (3 windows two 3.5 and a 5x5)with wooden frames! I couldn't be in my living room for 4 months of the year without looking like an Eskimo. Plus it was noisy as I live on a busy street. I found a company that installs replacement windows that are double pane with low e and one pane that is 3/16th" thick. The extra thickness is terrific in blocking noise. The replacement windows do not require you to remove any exterior trim, provided your existing windows are not surface nailed to begin with. Simply remove the stops on the inside, remove old, replace with new and replace wood stops. Whoalla! New warm quiet windows in about an hour. Suddenly my heat bills plummeted and I could lounge in my T-shirt in the living room in the dead of "winter."  

It might be worth it to take out a small line of credit or loan to do the replacements and see the heat and or cooling savings help pay off the loan! Check locally to see if there is a "Homeworks" or similar company that advertizes "replacement" windows. I was so thrilled I replaced all my office windows (1920's bungalow)and had the same wonderful results.

A caveat here, the only actually affordable windows other than leaky aluminum ones are made out of vinyl. I know that Umbra would never use them, but please consider they are made in a more environmentally responsible manner now in the US and will last basically forever, which is a good thing. The key is a "thermal block" between inside and outside which vinyl and wood can easily do. Problem is that wood windows are many times more expensive for us mere mortals.

PS, Plastic with tape and or storm windows will not come close to helping solve this problem.

K. Austin, Architect

]]> Cold Windows

I too live in a realtively mild CA climate and own a very old home. It took me several years to have enough money to replace the large original plate glass windows in my living room. (3 windows two 3.5 and a 5x5)with wooden frames! I couldn't be in my living room for 4 months of the year without looking like an Eskimo. Plus it was noisy as I live on a busy street. I found a company that installs replacement windows that are double pane with low e and one pane that is 3/16th" thick. The extra thickness is terrific in blocking noise. The replacement windows do not require you to remove any exterior trim, provided your existing windows are not surface nailed to begin with. Simply remove the stops on the inside, remove old, replace with new and replace wood stops. Whoalla! New warm quiet windows in about an hour. Suddenly my heat bills plummeted and I could lounge in my T-shirt in the living room in the dead of "winter."  

It might be worth it to take out a small line of credit or loan to do the replacements and see the heat and or cooling savings help pay off the loan! Check locally to see if there is a "Homeworks" or similar company that advertizes "replacement" windows. I was so thrilled I replaced all my office windows (1920's bungalow)and had the same wonderful results.

A caveat here, the only actually affordable windows other than leaky aluminum ones are made out of vinyl. I know that Umbra would never use them, but please consider they are made in a more environmentally responsible manner now in the US and will last basically forever, which is a good thing. The key is a "thermal block" between inside and outside which vinyl and wood can easily do. Problem is that wood windows are many times more expensive for us mere mortals.

PS, Plastic with tape and or storm windows will not come close to helping solve this problem.

K. Austin, Architect

]]> Comment #2 by willa http://www.grist.org/article/inefficient_windows/ Wed, 08 Nov 2006 23:20:16 -0800 http://www.grist.org/article/inefficient_windows/2 new not necessarily better

From NPS preservation brief 9:

Many styles of storm windows are available to improve the thermal performance of existing windows. The use of exterior storm windows should be investigated whenever feasible because they are thermally efficient, cost-effective, reversible, and allow the retention of original windows (see "Preservation Briefs: 3"). Storm window frames may be made of wood, aluminum, vinyl, or plastic; however, the use of unfinished aluminum storms should be avoided. The visual impact of storms may be minimized by selecting colors which match existing trim color. Arched top storms are available for windows with special shapes. Although interior storm windows appear to offer an attractive option for achieving double glazing with minimal visual impact, the potential for damaging condensation problems must be addressed. Moisture which becomes trapped between the layers of glazing can condense on the colder, outer prime window, potentially leading to deterioration. The correct approach to using interior storms is to create a seal on the interior storm while allowing some ventilation around the prime window. In actual practice, the creation of such a durable, airtight seal is difficult.

...

Consider energy efficiency as one of the factors for replacements, but do not let it dominate the issue. Energy conservation is no excuse for the wholesale destruction of historic windows which can be made thermally efficient by historically and aesthetically acceptable means. In fact, a historic wooden window with a high quality storm window added should thermally outperform a new double-glazed metal window which does not have thermal breaks (insulation between the inner and outer frames intended to break the path of heat flow). This occurs because the wood has far better insulating value than the metal, and in addition many historic windows have high ratios of wood to glass, thus reducing the area of highest heat transfer. One measure of heat transfer is the U-value, the number of Btu's per hour transferred through a square foot of material. When comparing thermal performance, the lower the U-value the better the performance. According to ASHRAE 1977 Fundamentals, the U-values for single glazed wooden windows range from 0.88 to 0.99. The addition of a storm window should reduce these figures to a range of 0.44 to 0.49. A non-thermal break, double-glazed metal window has a U-value of about 0.6.

(emphasis added)

]]> new not necessarily better

From NPS preservation brief 9:

Many styles of storm windows are available to improve the thermal performance of existing windows. The use of exterior storm windows should be investigated whenever feasible because they are thermally efficient, cost-effective, reversible, and allow the retention of original windows (see "Preservation Briefs: 3"). Storm window frames may be made of wood, aluminum, vinyl, or plastic; however, the use of unfinished aluminum storms should be avoided. The visual impact of storms may be minimized by selecting colors which match existing trim color. Arched top storms are available for windows with special shapes. Although interior storm windows appear to offer an attractive option for achieving double glazing with minimal visual impact, the potential for damaging condensation problems must be addressed. Moisture which becomes trapped between the layers of glazing can condense on the colder, outer prime window, potentially leading to deterioration. The correct approach to using interior storms is to create a seal on the interior storm while allowing some ventilation around the prime window. In actual practice, the creation of such a durable, airtight seal is difficult.

...

Consider energy efficiency as one of the factors for replacements, but do not let it dominate the issue. Energy conservation is no excuse for the wholesale destruction of historic windows which can be made thermally efficient by historically and aesthetically acceptable means. In fact, a historic wooden window with a high quality storm window added should thermally outperform a new double-glazed metal window which does not have thermal breaks (insulation between the inner and outer frames intended to break the path of heat flow). This occurs because the wood has far better insulating value than the metal, and in addition many historic windows have high ratios of wood to glass, thus reducing the area of highest heat transfer. One measure of heat transfer is the U-value, the number of Btu's per hour transferred through a square foot of material. When comparing thermal performance, the lower the U-value the better the performance. According to ASHRAE 1977 Fundamentals, the U-values for single glazed wooden windows range from 0.88 to 0.99. The addition of a storm window should reduce these figures to a range of 0.44 to 0.49. A non-thermal break, double-glazed metal window has a U-value of about 0.6.

(emphasis added)

]]> Comment #3 by kellya http://www.grist.org/article/inefficient_windows/ Tue, 14 Nov 2006 06:03:56 -0800 http://www.grist.org/article/inefficient_windows/3 Chilly Screens of Winter

We live in a 115 year old house in Denver, CO.  I can testify that rehabbing the original wood windows and adding good quality storm windows are great ways to reduce heat loss through the windows.  We are gradually rehabbing the existing windows (replacing cracked panes, new caulk, weatherstripping, ensuring tight fit) and are getting new storms (wood frames with exchangeble screen/glass panels) made.  The temperature (and noise) control in the rooms that have rehabbed windows is very noticably improved compared to those rooms yet to be done.  Plus, the look is wonderful -- very compatible with the historic appearance of our house.  I can't speak to price comparisons -- we never considered replacing the windows due to their historic nature.

]]> Chilly Screens of Winter

We live in a 115 year old house in Denver, CO.  I can testify that rehabbing the original wood windows and adding good quality storm windows are great ways to reduce heat loss through the windows.  We are gradually rehabbing the existing windows (replacing cracked panes, new caulk, weatherstripping, ensuring tight fit) and are getting new storms (wood frames with exchangeble screen/glass panels) made.  The temperature (and noise) control in the rooms that have rehabbed windows is very noticably improved compared to those rooms yet to be done.  Plus, the look is wonderful -- very compatible with the historic appearance of our house.  I can't speak to price comparisons -- we never considered replacing the windows due to their historic nature.

]]> Comment #4 by Hugh H http://www.grist.org/article/inefficient_windows/ Fri, 17 Nov 2006 00:12:26 -0800 http://www.grist.org/article/inefficient_windows/4 High Windows

I lived in a victorian house for nearly twenty years. The main ground floor reception rooms all had huge expanses of glass in the original wooden frames. When we moved in we found that the previous owners had fitted large sheets of glass which acted as crude secondary double glazing. These were removeable for the summer months. After we moved on the house was converted into flats and new replacement windows fitted throughout.

Hugh

]]> High Windows

I lived in a victorian house for nearly twenty years. The main ground floor reception rooms all had huge expanses of glass in the original wooden frames. When we moved in we found that the previous owners had fitted large sheets of glass which acted as crude secondary double glazing. These were removeable for the summer months. After we moved on the house was converted into flats and new replacement windows fitted throughout.

Hugh

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