Don’t let yourself think of existing walls as immutable or hyper-focus your attention on the surface of things. Gilding the lily won’t fix an awkward, dark or segmented floor plan.
You can get a big win from a small change in layout
While you should take the opportunity to improve all kinds of layout flaws – tight corners, inadequate kitchen storage, not enough privacy for bedrooms, etc – focus on layout changes that will improve your relationship with the sun.
It is true that designing for daylight is one area where building new can be easier to accomplish than it is in a remodeling project. When you start from scratch, you can choose your site and orientation with the sun in mind. With an existing home you get what the original builder gave you in terms of solar access.
Don’t worry. You can still make improvements … you’ll just have to be creative to get the best result.
Where do you stand?
Start by assessing your solar gain situation. When are the hot and cool times of day and year and where does the sun hit your home at those times? When does direct sunlight shine into (or hit the outside of your house)?
In order to take advantage of solar heat gain you want to: allow sunlight to enter the house strategically and direct it to a heat-absorbent thermal mass.
On the other hand, to take advantage of passive cooling you will: block sunlight from entering the house and take advantage of stack effect air circulation.
In both cases you will need adequate insulation to extend the heat or cooling you collect under favorable conditions through the 24 hour period.
Achieving a balanced heat gain can prove tricky since the same mid-angled sun and mid-range day length that gives you a boost of welcome spring warmth in March can be devastatingly hot in a warm September. A combination of large southern windows and adjustable shading devices will take you in the right direction.
Rule of Thumb:
Tip your daylight early. In other words, you want to focus on letting light shine into your house during morning and mid day AND during winter and spring and keeping out the overheating light of late afternoon and of the high summer and fall.