[MassHistPres] More window material

Sat Sep 26 11:23:22 EDT 2009

Don't forget that many storm windows also qualify for the $1500 tax 
rebate that the replacement window proponents are pushing.

Kristi Chase
Somerville

Alison Hardy wrote:
> Just point of information, going rate for installed Harvey Tru-Channel 
> storm windows with Low E glass is around $250 each. Typical cost for 
> weather stripping, cord replacement, patch glazing, etc is around 
> $200-300 per window.
>
> There ought to be a whole lot more noise about storm windows. They are 
> by far one of the best investments a homeowner can make.
>
> Alison Hardy
>
> Dennis De Witt wrote:
>> I agree.  
>>
>> What seems to be missing is the alternative of installing high 
>> quality storms (e.g. Harvey tru-channel) w/ or w/out low-e.  They 
>> should have an infiltration number comparable to the IG replacement 
>> windows and the U value probably wont be much different than what you 
>> would see for the typically generic IG used on cheap vinyl sash.  So, 
>> you can spend maybe $150 per window on the storms, save the original 
>> windows (and maybe spend $150 per window on average tightening them 
>> up) and not have something that will fail in 20 years.
>>
>> Why can't the National Trust or the NPS contact this state government 
>> agency and get them to incorporate storm windows into their equation? 
>>  -- in two places a) factor them in to the "before" figure if they 
>> already are in place & b) offer them as an alternative to 
>> replacements for the "after" figure.
>>
>> Dennis De Witt
>> Brookline.
>>
>>
>> On Sep 25, 2009, at 2:06 PM, Michael Smith wrote:
>>
>>> Our advice to homeowners is to rehabilitate existing historic single 
>>> pane windows and install new storm windows to gain energy 
>>> efficiency.  This seems to be a common suggestion in much of the 
>>> literature on historic window restoration.  Comparing the 
>>> infiltration rate of an old wood window with that of a new 
>>> insulating glass, energy-efficient window, without factoring in a 
>>> new storm window seems inconsistent with most recommendations.  Or 
>>> am I missing something?
>>>  
>>> Michael Smith, Co-Chair
>>> Belmont Historic District Commission                      
>>>  
>>> ------------------------------------------------------------------------
>>> *From:* Chris Skelly [mailto:Skelly-MHC at comcast.net] 
>>> *Sent:* Friday, September 25, 2009 1:57 PM
>>> *To:* masshistpres at cs.umb.edu <mailto:masshistpres at cs.umb.edu>
>>> *Subject:* Re: [MassHistPres] More window material
>>>  
>>> I think making any assumptions on the "infiltration" factor of an 
>>> old window demonstrates that this worksheet is misleading.   Just 
>>> because a window is old doesn't mean it has to leak air. 
>>>  
>>> Would we use this logic to demonstrate how much money we would save 
>>> by buying a new car?  If comparing how much money you would save on 
>>> automobile fuel, you would need to consider the miles per gallon of 
>>> the old car and the miles per gallon of the new car.  All old cars 
>>> don't have the same miles per gallon and all old windows shouldn't 
>>> be treated with such a broad brush either.  Furthermore, the 
>>> infiltration that will occur over time with a new vinyl replacement 
>>> that warps and bends needs to be factored here as well.  
>>>
>>> When it comes to saving energy on heating a home, infiltration is a 
>>> major issue that needs to be addressed.   Yet when it comes to old 
>>> wood windows, infiltration can be addressed very effectively through 
>>> a number of methods.  Methods such as installing removable rope 
>>> caulk each fall are very inexpensive.  For those on a tight budget 
>>> and faced with leaky windows, this can make a huge difference.  Chris.
>>>
>>> Christopher C. Skelly 
>>> Director of Local Government Programs 
>>> Massachusetts Historical Commission  
>>> 220 Morrissey Boulevard, Boston, MA 02125 
>>> Ph: (617) 727-8470 / Fax: (617) 727-5128  
>>> Christopher.Skelly at state.ma.us <mailto:Christopher.Skelly at state.ma.us> 
>>> http://www.sec.state.ma.us/mhc/mhcidx.htm 
>>> *******Stay Informed on Historic Preservation Topics by joining the 
>>> MassHistPres Email List. 
>>> Visit http://mailman.cs.umb.edu/mailman/listinfo/masshistpres for 
>>> more information. ******MHC offers regional training workshops to 
>>> local historical commissions and historic district commission 
>>> members on a variety of topics. ******The MHC has a new 50 minute 
>>> DVD for Local Historical Commissions. ******The Local Preservation 
>>> Update is MHC's new bi-weekly e-newsletter.  For more information on 
>>> any of the above, please contact me. 
>>>
>>> -----Original Message-----
>>> *From:* masshistpres-bounces at cs.umb.edu 
>>> <mailto:masshistpres-bounces at cs.umb.edu> 
>>> [mailto:masshistpres-bounces at cs.umb.edu]*On Behalf 
>>> Of *slater at alum.rpi.edu <mailto:slater at alum.rpi.edu>
>>> *Sent:* Friday, September 25, 2009 12:04 PM
>>> *To:* masshistpres at cs.umb.edu <mailto:masshistpres at cs.umb.edu>
>>> *Subject:* Re: [MassHistPres] More window material
>>>  
>>> Maybe someone can help me out here. I just did this worksheet for 
>>> window replacement:
>>>
>>> http://www.dnr.mo.gov/forms/780-1363.pdf
>>>
>>> Based on my calculations, it told me that a house with 30 single 
>>> pane windows with storms will consume 582 gallons of oil -- just for 
>>> the windows -- and that if you install low-E replacements, it would 
>>> consume just 233 gallons of oil just for the windows. Replacing 
>>> would save 439 gallons of oil annually.
>>>
>>> Let me tell you my assumptions and maybe someone else can try this.
>>>
>>> First, I assumed 30 windows at 32" x 62" -- each being 13.9 square 
>>> feet. That's about the size of my second floor windows. Multiplied 
>>> by 30, that's 417 square feet of windows. 
>>>
>>> Second, I used 0.5 U-value for single pane with storms, 0.38 for 
>>> double-pane with low-E glass. That's an agreed upon number.
>>>
>>> I used the "degree days" method in line 6, since this form is 
>>> for Missouri and we are in Massachusetts. The calculation says 
>>> "degree days x 24 / 10^6". I used 6250 degree days, a number I got 
>>> from an energy website. That changed the factor to 0.15 versus the 
>>> 0.1 for Missouri.
>>>
>>> I used an energy cost of $19.73 per million BTUs. That was based on 
>>> oil being $2.75 per gallon. It came from this website:
>>>
>>> http://energy.cas.psu.edu/costcomparator.html
>>>
>>> I treated the fuel efficiency as 100% in the calculation because the 
>>> energy cost from the previous step already factored that in.
>>>
>>> I assumed that a vinyl replacement window costs $300 installed.
>>>
>>> Using the formula on the spreadsheet, it said that if I keep the 
>>> original 30 windows, I will spend $1,849 in heating costs, and if I 
>>> replace them, I will pay $641 in heating costs.
>>>
>>> If that's true, that seriously weakens the argument for keeping the 
>>> originals pretty significantly -- if a replacement window costs 
>>> $300, then payback period is just 7 years. If oil goes up by 45% to 
>>> $4/gallon, then the payback period is just 5 years.
>>>
>>> One big factor is that the calculation uses something relatively new 
>>> (it wasn't on an earlier version of the form) called an 
>>> "infiltration factor". It is set to 1.00 for old windows, 0.14 for 
>>> new windows. That seems a little arbitrary, and it completely 
>>> changes the results of the calculation. Without this factor, a 
>>> replacement window without low-E glass is actually less efficient 
>>> than an original window with storms. 
>>>
>>> I did some research on "low-E" -- there is some thought that it does 
>>> not last for the life of the window, and may only last for 5-6 years 
>>> before breaking down. 
>>>
>>> Can someone else validate my numbers? Honestly, they are just not 
>>> that believable. I have 49 windows in my house -- some of them are 
>>> quite leaky, such as leaded glass casement windows -- with storms, 
>>> though the leaded glass transoms above them don't have storms. I 
>>> also have several windows without storms -- two 2nd floor bathroom 
>>> windows and a casement window over the kitchen sink, plus a fixed 
>>> window with multiple lights, plus a couple of 3rd floor casements 
>>> that open inward. Many of my windows are larger than the example I 
>>> used too.
>>>
>>> I use about 1,200 gallons of oil per year to heat a 4,000 square 
>>> foot house to around 65 degrees. If I plug 50 windows into to this 
>>> worksheet, it says 1,100 gallons of that is due to the windows, and 
>>> I would save 718 gallons per year by replacing them.
>>>
>>> I just can't believe that on its face. Could these calculations be 
>>> designed to justify replacement?
>>>
>>> Ralph Slate
>>> Springfield, MA
>>> ******************************
>>> For administrative questions regarding this list, please 
>>> contact Christopher.Skelly at state.ma.us 
>>> <mailto:Christopher.Skelly at state.ma.us> directly.  PLEASE DO NOT 
>>> "REPLY" TO THE WHOLE LIST.
>>> MassHistPres mailing list
>>> MassHistPres at cs.umb.edu <mailto:MassHistPres at cs.umb.edu>
>>> http://mailman.cs.umb.edu/mailman/listinfo/masshistpres
>>> ********************************
>>
>> ------------------------------------------------------------------------
>>
>> ******************************
>> For administrative questions regarding this list, please contact Christopher.Skelly at state.ma.us directly.  PLEASE DO NOT "REPLY" TO THE WHOLE LIST.
>> MassHistPres mailing list
>> MassHistPres at cs.umb.edu
>> http://mailman.cs.umb.edu/mailman/listinfo/masshistpres
>> ********************************
>>   
> ------------------------------------------------------------------------
>
> ******************************
> For administrative questions regarding this list, please contact Christopher.Skelly at state.ma.us directly.  PLEASE DO NOT "REPLY" TO THE WHOLE LIST.
> MassHistPres mailing list
> MassHistPres at cs.umb.edu
> http://mailman.cs.umb.edu/mailman/listinfo/masshistpres
> ********************************
>   