1. Weather
As I mentioned, one thing you want to think about is the weather conditions. In many places like the Pacific Northwest or the Northeast US, it can be pretty rainy for months on end and there is rarely a day that's totally dry. On the other hand, it may be mild and sunny but still plenty moist throughout the year. So what do you need your windows for then? You'll want to make sure you have a window system that has been designed with your climate in mind.
2. Your Climate
When looking at windows, make sure you have an idea of what type of climate you live in as well as what kinds of weather patterns/habitats your area exhibits. Don't get caught up in the numbers like percent of annual rainfall or humidity - they won't give you a clue on what type of window system you need. Instead, think about the types of conditions (wet vs moist) that are most common in your area. There are many different ways that windows can be designed - but the more specific you can be, like "warm and moist" or "drizzle and damp", the more beneficial it will be.
3. Appropriate Windows For Your Climate
When looking at windows to choose from, they'll often be described by their climate classification: Low-E, argon gas, or triple-pane. But these descriptions don't necessarily tell you the whole story about how the window will work for your conditions. For example, on a warm and moist day, you may want something that keeps those wet contents enclosed. So you'll want to look at the 'water retention' rating when choosing your windows.
4. Point Of Failure
When choosing the right windows for your climate, it is also important to consider how they can fail. Oftentimes, windows with aluminum frames will corrode or rot in wet climates. Regardless of the material used, if you have a lot of moisture and heat in your area, then you'll want to take this into account when choosing your windows.
5. Energy Efficiency
If you're going to have windows that are sealed off from the outside and in (either fully or partly) then they will produce a lot less heat than if they are open to the outdoors. This can make it more expensive to heat your home or pay for supplemental heating during the winter months. If you want to save money on fuel costs by simply sealing off ventilation systems and windows, then consider some insulation as well - adding thickness can help reduce energy use.
6. Total Cost Of Ownership
Now that we've looked at the basics about how windows work in your climate, what's their total cost of ownership? That is, how much do you expect to pay to replace them from now until they finally give out? There's a huge difference between an aluminum-clad window and a wood window in this regard. Doors are another part of your home that you'll want to consider - the right door can help insulate your home and save on heating bills as well.
7. Water Retention Ratings
If it rains frequently in your area or if there are high levels of moisture outside then you'll want some windows with a good water retention rating. Water retention ratings are spelled out as AH, AR, or HA on the window hardware and will tell you how much water a given window can retain. You'll want to make sure you get windows that have a high water retention rating to keep those wet, humid conditions inside.
8. No Maintenance Required
This one is important if you want something that doesn't require a whole lot of maintenance over time. Many of today's windows are very low maintenance and require nothing more than an occasional cleaning. If you want something that will keep your home dry, then you'll want windows that you won't need to replace at a premium cost.
9. Types Of Materials
There are many different types of materials that can be used in your window and the selection really depends on the temperature, moisture, and other conditions in your area. As I mentioned earlier, aluminum can corrode or rot if exposed to too much humidity while wood or fiberglass will warp or crack if it gets too hot or wet. There are many other varieties as well - each one requiring different types of care and maintenance in order to last a long time.
10. Energy Efficiency Ratings
This is one of the most important factors to consider when looking at windows - and their energy efficiency levels. Right now, most windows are only rated for their energy efficiency after they have been installed and no longer have a way to make adjustments like you can with sealed doors. While that might be fine in many climates, it won't be okay in others. Your windows should be able to keep your home dry and heat efficient. Otherwise, you may not be saving anything at all.
11. Installation
Some windows can be difficult to install and some require special tools to properly install them. You want something that is easy to install and won't take long before it's finished. A slow-to-install window likely won't last as long as a quick-to-install window will and may cost more in the long run.
Final Thoughts
As you can see, there are many different things to consider when getting windows for your home. The more information you have about the climate and conditions in your area, the better equipped you'll be to buy the right windows for your needs. If you don't take these factors into account then you may end up with a window that doesn't fit the kind of weather patterns that you have to deal with in your area. This could mean an expensive (and dangerous) window installation in the future - or worse yet, risk of flooding or water damage throughout your home.