Painted white roof drops house temps 8-10 degrees - Page 6

mariepsych · 08-05-12, 04:40 PM

Shall I go with a silver birch colored Certain tweed roof? How much cooler would it make the house in the summer and how about heat holding capacity in the winter. I live in a mild climate in bay area California, but it does get in the low 100s and 90's sometimes in the summer during the day with cool nights. I am concerned about the "look" of silver birch but really want the house to be a cool as possible so I don't need AC and I don't want to spend the $ for Solaris and don't know that they will hold up over time. I struggle with the curb appeal concept but maybe there will be a trend to lighter colored roofs in the future as the price of energy goes up.

amber12 · 09-12-12, 06:35 AM

This seems great but I have a question. If it decrease temperature in summers then won't it like increase it in winters? I mean won't the house be colder in winters?

Daox · 09-12-12, 08:19 AM

Yes, it will. However, if you have enough attic insulation the effect should be minimized in either scenario.

MN Renovator · 09-12-12, 08:39 AM

Keep in mind, it won't matter what color your roof is in the winter once it has been painted white with snow. ..unless you are in a climate with little snow in the winter but I don't think I can include Ontario in that. I think you'd be better off to plan for the summer in this case.

NeilBlanchard · 09-12-12, 09:12 PM

Also, the low angle of the sun in the winter and the limited daylight means that you "lose less" in the winter, so overall you can save a LOT more energy in the summer than you lose in the winter.

philhersey · 04-21-14, 06:43 PM

I took a backpack sprayer from harbor freight mixed 50% water 50% water based white opaque wood stain and then dusted my roof to lighten the shade...worked fine less stark than pure white. But now in summer I'm going to try the temporary hydrated lime whitewash I saw in earlier post! Sounds perfect.

Daox · 04-22-14, 08:44 AM

Welcome to the site Philhersey.

How well did the wood stain work for you?

natethebrown · 04-22-14, 09:49 AM

I wonder if adding pigments, like a light gray pigment, would help the "desirability" of doing this on dark gray/black roofs? Since I am a youngster by most of your standards, I am not familiar with lime-washes. Doing some research, it does appear pigments in a lime-wash is very common.

philhersey · 04-22-14, 01:13 PM

Quote:

Originally Posted by Daox

Welcome to the site Philhersey.

How well did the wood stain work for you?

.... it worked fine to lighten the shade a lot from black to light grey. It's been up there two years no problems, stays on, stays white. I painted two shingles 100% in a place not seen from street and they are fine too. Looks ok, not great, but better than if I had painted entire roof stark white.

BeeHappy · 05-13-16, 03:13 PM

Hi Mobile Master Tech,

Thank you so much for the detailed info on your certainteed silver birch roof. I'm considering to reroof with exact same material as yours. May I please ask:
- How well does your roof hold up?
- How much energy savings do you see on your bill in summer time?
- Do you see any increase in energy bill in winter time? since the roof reflects sunlight, I wonder if it makes house colder in winter.

Thanks,

Quote:

Originally Posted by Mobile Master Tech

It's actually a pleasing light gray. Wish the picture did it justice. Most white roofs are very... well, WHITE, and they tend not to stay that way. You're welcome to come look, but it looks like your trip would be a bit long!

Many home improvement stores have a large sample patch installed on the wall and smaller sample boards you can take home with a deposit. Since you aren't in the US, the specification you are looking for is "Initial Solar Reflectance". Energy star criteria are that this number must be at least 0.25 and maintain 0.15 SR after 3 years. Mine are 0.27, higher is better.

Landmark Solaris Platinum shingles from Certainteed have an ISR of 0.40 but are $$$ because of higher cost per square and more bundles to cover 1 square.

09-12-12, 08:19 AM	#53
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	Yes, it will. However, if you have enough attic insulation the effect should be minimized in either scenario. __________________ Current project - To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. & To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

04-22-14, 08:44 AM	#57
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	Welcome to the site Philhersey. How well did the wood stain work for you? __________________ Current project - To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. & To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

08-05-12, 04:40 PM	#51
mariepsych Lurking Renovator Join Date: Aug 2012 Location: bay area california Posts: 1 Thanks: 3 Thanked 0 Times in 0 Posts	Shall I go with a silver birch colored Certain tweed roof? How much cooler would it make the house in the summer and how about heat holding capacity in the winter. I live in a mild climate in bay area California, but it does get in the low 100s and 90's sometimes in the summer during the day with cool nights. I am concerned about the "look" of silver birch but really want the house to be a cool as possible so I don't need AC and I don't want to spend the $ for Solaris and don't know that they will hold up over time. I struggle with the curb appeal concept but maybe there will be a trend to lighter colored roofs in the future as the price of energy goes up.

09-12-12, 06:35 AM	#52
amber12 Lurking Renovator Join Date: Sep 2012 Location: Ontario Posts: 3 Thanks: 0 Thanked 0 Times in 0 Posts	This seems great but I have a question. If it decrease temperature in summers then won't it like increase it in winters? I mean won't the house be colder in winters?

09-12-12, 08:39 AM	#54
MN Renovator Less usage=Cheaper bills Join Date: Nov 2010 Location: Minneapolis, MN Posts: 940 Thanks: 41 Thanked 117 Times in 91 Posts	Keep in mind, it won't matter what color your roof is in the winter once it has been painted white with snow. ..unless you are in a climate with little snow in the winter but I don't think I can include Ontario in that. I think you'd be better off to plan for the summer in this case.

09-12-12, 09:12 PM	#55
NeilBlanchard Journeyman EcoRenovator Join Date: Dec 2009 Location: Maynard, MA Eaarth Posts: 383 Thanks: 78 Thanked 39 Times in 32 Posts	Also, the low angle of the sun in the winter and the limited daylight means that you "lose less" in the winter, so overall you can save a LOT more energy in the summer than you lose in the winter.

04-21-14, 06:43 PM	#56
philhersey Lurking Renovator Join Date: Apr 2014 Location: carson city, nevada Posts: 2 Thanks: 0 Thanked 1 Time in 1 Post	I took a backpack sprayer from harbor freight mixed 50% water 50% water based white opaque wood stain and then dusted my roof to lighten the shade...worked fine less stark than pure white. But now in summer I'm going to try the temporary hydrated lime whitewash I saw in earlier post! Sounds perfect.

04-22-14, 09:49 AM	#58
natethebrown Apprentice EcoRenovator Join Date: Aug 2012 Location: North Alabama Posts: 167 Thanks: 0 Thanked 40 Times in 20 Posts	I wonder if adding pigments, like a light gray pigment, would help the "desirability" of doing this on dark gray/black roofs? Since I am a youngster by most of your standards, I am not familiar with lime-washes. Doing some research, it does appear pigments in a lime-wash is very common.