2020 Boise Idaho Real Estate Blog
the disappearance of the roof overhang Main The Durable Green Home
Isn't the roof overhang just costing me extra?

So  why would you design a home or pay for wider overhangs on your  roof? Don't they just cost you extra? What is the purpose?

this is one of the key elements of building durability and energy efficiency. The overhand is designed to shed the roof water away  from the building and foundation. Why might you ask? because the more water you have running  down the siding ( siding is not water proof) the higher the chances are for water intrusion, the faster the paints and siding will deteriorate, the higher the chances for water to enter in doors and windows. Also if the water is dropped right at the foundation, what are the chances it will migrate inside the crawl space, splash the siding, or stone. do you know that when a stone (brick, masonry, etc) gets wet and sun hits the wet surface it literally drives the moisture inside the wall? this will happen in seconds. so the more water we  keep off the assemblies the better. Also how many times have you seen contractors compacting the backfill against the foundation to reduce settling over time? Can you say hardly ever? over  time the dirt next to the foundation settles (take  a look at your own home) creating a slope back to the foundation instead of away from it. the closer the drip line ( water falling from roof) the higher the  chances the soil will  compact  and water will flow to the foundation. over a period  of years, usually with  new homes  3-5 years the water will  start to migrate inside  the crawl space (look for water lines or  lime deposits (white) inside the crawl, over the footing where the metal cleats separate  the stem wall  from the footing, against the bottom of footings. this will tell you the crawl gets wet from time to time.  In newer homes this  can lead to big Problems fast.

Also what about shading?  overhangs less  than two feet will not  shade your  windows from solar gain in the summer. An Architect can help you with this. most or  all of your west and south facing glass  should be shaded by the overhang if possible. How many homes do you see with one foot  overhangs and huge amounts of glass facing south or west? Why does this matter?

this will create huge heat load gains in the summer you will  have to overcome with air conditioning, you are paying for larger equipment costs than needed because of poor design or orientation,  if the house had proper overhangs the equipment costs  difference would pay for the wider roof, ( of course this means the HVAC contractor must understand proper heat load calculations using manual J room to room  breakdown), interior furnishings will fade faster causing you to replace them sooner. Look at the next house you see from this perspective, you will start to ask questions also.

Posted by Tad Duby at 3/1/2008 6:04:00 PM
Comments (2)
Re:the disappearance of the roof overhang

Thank you for demonstrating the importance of large eves and barges (overhangs). From day one all of my homes have come standard with 24 inch eves and barges. We even have a home plan where we use 36 inch eves and this is on a plan that is less than $235K.

Not only is it considered a green design element, but the curb appeal obtained from using large eves is phenomenal. Especially if you install a raked eve system instead of a bird-boxed system, which the bird-boxed system adds bulkiness and clutter to the appearance.

The more we can improve the durability and curb-appeal of the homes in the Treasure Valley the more enjoyable place it will be to live.

Scott Flynn, RMB
Posted by on 3/1/2008 3:18 PM
Re:the disappearance of the roof overhang
great comment on asthetics, these homes are more appealing, and designed correctly can be the same cost or less than homes without appropriate overhangs. Funny that the older homes took this into consideration in the design and building of the homes. I sometimes wonder when did we loose site of the basics of home design and function?
Posted by on 3/3/2008 5:19 AM
Add Comment
Provide comments on this blog entry. If you have an account with this site please sign in.
*Title *Email Web Address *Comments


Michelle Penick, Build Idaho Client Real Estate Services

Michelle Penick

Client Care Team
[email protected]

Schedule Tour

Get a Community Recommendation

★★★★★ 5 stars - "Our experience with Full Sail/ Build Idaho was great from start to finish! "