An Addendum To The Replacement Window Debate

I admit I have been blog-crastinating (Blog-deficient, blogligent, feel free to add your own made up words in my comment section). I got the new iPhone on Monday and it truly has been a time sucker, man! As well as being very busy with home inspection stuff I’m happy to admit. Anywho, a couple of weekends ago in my quest to turn my 1923 Clintonville home into something that didn’t leak heat like a sub with a screen door leaks water, I decided to replace my basement windows. I know, I know. I am against replacement windows on an old home if they are in good shape, fully functional and you can add storm windows to them (see ) because I believe that it ruins the aesthetics and the charm of an old home. That being said, I wanted basement windows that could open and close, did not want to make storm windows for a feature of the house that is of little consequence but did NOT want glass block because they are ugly and industrial looking. I’m a complicated man, just ask my wife. So I got custom replacement windows from my favorite window guy. If you are in the area and you decide to get new windows I highly recommend Brian at Exterior Building Supplies at (614) 784-8330. It is his company and he is incredibly helpful. I have bought probably over 100 windows from him over time and NEVER been dissatisfied.

So I bought sliders, which means that they open from left to right instead of up and down. They have a built-in screen, insulated glass and low E argon gas inside the insulated glass. They also fit the look of the house much better than other options. Although this post seems like a pandering plug for a window company, I actually thought this would be a good article for a couple of reasons. First of all, if you really do want to put in replacement windows in your house because the current windows are in very poor shape or you are just a sell-out (jk) than this would be a good intro because this is a stupidly easy project for the most part. Homeowners can save a bunch of $$ doing this themselves. Secondly, this will lead into my next tool spotlight in my monthly Tool Porn article (the folding/sliding ruler). This was also a great chance to do some experiments to gauge what kind of insulating effect it had on my home, a sort of “bang for the buck” type thing.

My old three light basement window. Single pane glass with no screen or storm window.

So for the instructional part. The first step is extremely easy for a basement window. For a double hung window in your house it will be a bit more complicated. You need to take a pretty precise measurement of side to side and up and down. With my basement window I just open the window and go for it ’cause there is nothing in the way, it is a clean rectangle wood frame and the current window will be gone. For a normal double hung you want to measure behind (to the inside) of the outside window stop strip. This strip is what the top window sash hits up against to keep it from falling outside. The rest of the stuff around the window frame, other than that strip, will be either removed or covered so you really don’t need to sweat it till install day. The other tricky part is where to measure for the up and down measurement because your window sill will slope down away from the house to shed rain water. If you find the thickness of the replacement window, measure back toward you from the outside window strip we spoke of earlier and measured up from there and you should be sittin’ pretty. Here is the supa-dupa important step. Once you have these two measurements, side to side and up and down, you need to take off about a 1/4″ from each measurement to facilitate insertion (That sounds sooo serious, facilitate insertion. Reminds me when I used to do a lot of commercial painting for work and when people would ask me what I did I would say that I was a pigment transfer engineer). These are the measurements you will give to your window person and also how they figure out the cost. They actually add these two measurements together to get your cost. Weird, I know. It’s not square footage. Hmmmmm. It is called the united inches, height plus width. Now order your windows and sit back and wait.


This photo shows the items which will need to be removed. My fingers point to the window stop trim on the right and the parting strip on the left. The parting strip goes between the upper and lower sashes. The sash cord will also need to be removed and the pulley possibly flattened if the window is snug.



When the day comes you will be removing the old windows, parting strips, sash cords, insulating in the pockets where the sash weights are, etc. You will also want a can or two (or more) of low expansion insulating foam. Low expansion is important so that it won’t over expand and bow out the window sides. The window will usually come with screws taped to it so that shouldn’t be a problem. Unfortunately it was the case for my basement windows because the screws provided were too long. The 3/4 inch wood frame had cinderblocks behind it and the screws were about 2-2 1/2 inches long. I needed shorter screws to go into the wood but not long enough that the cinderblocks stopped them. Oh yea, a cordless drill with a Phillips head attachement. If you don’t have that, log off your computer and immediately go out and buy one. Seriously, who doesn’t have one of those?!?! Jeez, almost forgot, a level and bullet level and wood shims also. It’s difficult to mentally go over the list! Your windows should fit in and up against the outside strip without falling out. If the sash pulleys get in the way you will have to hammer them flat. No turning back now so just go for it. With the window sitting in the rough opening the art begins. No house is ever perfectly level or plumb. Ever! You will now need to center the window in the hole with the shims to hold it steady and at the same time get the window level (using the bottom and top) and plumb (using the sides). Plumb means that the window is straight up and down and not leaning in or out at the top or bottom. The art comes in the compromise because older homes are not level and not plumb to some degree. You need to decide whether to split the difference with the window so the eye won’t pick up on the fact that your window is level and plumb but your house is not, completely stay true to plumb and level and make your house look out of wack or completely follow the dimensions of the house and have an out of plumb/level window. I personally like the compromise. Maybe it’s the Buddhist in me, always searching for the middle path. Once you figure this out you are going to insert four (Yes, just four) screws into the tops and bottoms of the side frames. I like to put my shims in these locations so the screws will hold the shims in place and the shims will keep the windows from being pulled into a parallelagram.  You will pull the shims out from the top and bottom and float the window in the space and cut off the excess where the shims are held in place by the screws. This allows for expansion and contraction of the wood frame and the low expansion foam will shore things up as well as the trim you will put around the window to make everything purdy. Between this trim and some caulk on the outside you should be good to go. It helps to install the window with it closed and locked by the way. Helps to keep the shape true while you are shimming and screwing (That almost sounds dirty and I kinda like it).

Now for the experiments! I put a piece of painters tape on the old window so I could measure the surface temp of the glass with my IR thermometer (See )  and the air temp within 4 feet of the window in my basement. After replacing the window and sealing the gaps with foam, I then took similar reading with the new window in place. Let me say that it was very revealing.


Data from the old window.

This shows that the surface temp of the old window was 39 degrees and the air temp in the basement was 56 degrees within 4 feet of the window. Now, after replacing the window here is the data from the new insulated glass replacement window.


Same data readings from new window.

In this paradigm shifting, completely elaborate experiment (just work with me, this blew me away but I am a simple man) the surface temp was now a wopping 54 degrees (15 degrees warmer) and the air temp was almost 61 degrees. The air was now 5 degrees warmer in my basement! Could I have achieved about the same results with a storm window, sure. The thing is I didn’t want to change out storms on basement windows every fall and spring, I wanted windows that could open and close easily and I didn’t feel in this instance that I was sacrificing any of the charm of original windows. As far as cost goes, these custom replacement windows probably came out cheaper than glass block after having to buy mortar and all the other extras and time-wise and effort-wise there is NO comparison between the two. I have done glass block before and besides being messy it is just not fun and it’s heavy and cumbersome. I’d rather have to drink cheap beer than do glass block again (Did I just say that!?).


Replacement window installed but not trimmed out.


Picture of window with the right sash open. Easy peasy lemon squeezey.


Pha-shew. Finally jumped back into posting. Sorry for the delay. I think I need to pick some easier topics for a bit. Maybe some video posts so I don’t have to type.

Anyway, hope you enjoyed and hopefully learned.

Thanks for reading,


That Home Inspector Guy









About Travis "That Home Inspector Guy" Moyer

I am a certified home inspector, rehabber, landlord, carpenter, handyman and generally inquisitive person who wants to know how everything works. I love to educate other DIY homeowners and potential homeowners about projects that they may be interested in.

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