I am not a window expert just had to make window decisions. I replaced windows last fall and would have loved to have put in double hung, I have sliders, (I would have had to install 2 double hungs in the space where 1 slider was) the casements are the ones with the crank out right? I did put one casement over the kitchen window so it could be opened easier, it has two sections that crank out. I know the "crank out" are generally more expensive, more complicated window. I would think the double hung may be a bit more energy efficient. The casements you get a more unobstructive view. Decisions, decisions.

Another reason I wanted double hung is being able to crack open the top and bottom sections a bit for ventilation, even when raining. Be sure to get full screens if you want to do that. You could probably do that with casements too. I did get 2 double hungs on the side sections on my new bay window (could have gone with casements)

It really depends on the style of your home. To me, casements seem more 'modern', and double hung more 'classic'.

We have Casement and Double-Hung. I am no expert. The following is our experience and research info.

Good windows from reputable manufacturers, big or small, will seal well and not have unreasonable infiltration. A company may sell different lines from entry-level to higher-end and each line may have different infiltration rating. You can check the ratings published by the manufacturer to get one that best fits your requirements. In general, casement is supposed to seal better than dbl-hung and slider is supposed to be the hardest to seal tight. Again, good companies knows how to seal them tight, sliders or otherwise.

Draft in general has three sources. One is poorly sealed windows, another is poorly installed windows with gaps and seams open to the outside and the other is poorly constructed windows. A properly installed window can seal tight against infiltration but if it transmits heat or cold readily from the exterior to the interior due to poor design or material, then a draft will form as interior air passing the window is rapidly heated or cool. Either case, air movement will happen by the windows.

Note that "cheaper" windows often are poorly designed and constructed and will be drafty. We lived with a house full of these when we bought our place and ended up replacing all of them. So in many cases, we do pay for what we get.

Modern windows use all sorts of thermal breaks to limit or prevent such contact-transfer of thermal energy. Low-E coating is very effective at keeping heat out in the summer and warmth in during winter months. Double-pane construction with gas-filled space is another method to limit energy transfer. Ours are of such construction and have lived up to expectation.

We are currently smack dab in the middle of CA's Summit Fire that started last THursday. Our house has been covered by thick smoke all this time and no hint of smoke in our house yet. Both the dbl-hung and casement are doing their jobs.

Good luck with your research!

Woops! We are about 10 nautical miles SE of the fire and was in the middle of its smoke plume, NOT in the middle of the fire itself. Wife caught that! Sorry for misinfo.

If you are comparing the exact same window manuf. and the exact same line of windows with the same glass etc. Air infiltration rates starting from the lowest to the highest would generally be:

1. Picture window
2. Casement/Awning
3. Double Hung
4. Slider

This also assumes a high quality installation of all windows by an experienced and knowledgeable installer.

I prefer sliders because I can (and have) install exterior solar shades to prevent the extreme heat build up in the summer on the east, south and west facing windows. I'd rather prevent most of the sun's UV rays from even hitting the window pane than have to deal with the UV rays once they have entered the house.

With casement (these are the type that have the handle that can 'push' the pane away from the house, right?) you can't as far as I know install exterior solar blinds.

I've left a link in a few posts in above threads to the link to our blog post showing we obtained 15 degree F reduction in the temperature gauge if you think that they may work for you and therefore influence your decision on the type of replacement window.

Dan

Casement can indeed be used with external solar shades depending on installation and usage.

We have external solar shades that come down over our casements. The shade is in a case mounted on the wall of the house above the windows. When the sun is on that side of the house, it is hot and the windows are closed and the shade comes down to further reduce solar radiation hitting the windows. Why open the windows if the shade must come down? Won't that let in hot air anyway? Unless you are in mild climate zones where there is constant cool breezes even when the sun hits the windows and shade.

After sunset and before sunrise, our solar shade rolls up and the casement windows are open to capture and redirect cool morning and evening breezes into the house. This reduces A/C usage during hot weather.

So in our climate (northern CA), casement and solar shade can co-exist and work perfectly to meet our needs.

Phoggie,

If you purchase a quality window, it makes very little difference whether you choose casement or double hung. Drafts can be caused by air infiltration, but quality windows are designed to virtually eliminate air infiltration regardless of style. Many homeowners are surprised to learn that drafting is more often caused by inefficient windows. When the inside pane of glass on an inefficient window gets cold, and warm air in your home (usually coming from heat registers placed directly below windows) comes into contact with cold glass, it creates a "thermal draft." A thermal draft occurs when warm air cools quickly and drops, resulting in a cool air draft.

When it comes to drafting, you should be less concerned with the style of window than you are with the energy efficiency. Therefore, choose the style of window that bests suits your needs and make sure it is energy efficient. Be aware, however, that casement windows typically have more problems in the longrun due to more operating parts; they are also harder to clean than double hungs.

Good luck.

Casement windows are the best rated for air infultration,for windows that oparate.Look into triple pane option.

Here is a link that might be useful: window replacement Boston

there are positive and negatives to both windows. If you are looking for maximum light transmittance and maximum ventilation when the windows are open then Casements may be the way to go.

The drawback to casements on a first floor especially is that when they are open that may stick out into a trafic area on a deck or a patio or walkway. They are easier however to get to meet egress astandards on a casement especially now where if the window is more than 6 feet off the ground and closer than 24 inches to the floor new codes say restrictive opening hardware must be in place. It is very hard on a standard height second floor to meet this requirment with double hungs.

Double Hungs on the other hand allow you to open the top of the window and keep the bottom closed if you have little kids around and the window is to close to the floor. A double hung is much harder to get to meet egress standards which is 5.7 square feet of clear opening when the window is open.