Find out the best place to locate a skylight. Get tips on using filtered blinds to reduce solar heat in summer and buying high quality glass, which is more energy efficient.
TOM: This is The Money Pit Home Improvement Radio Show on air and online at MoneyPit.com. I'm Tom Kraeutler.
LESLIE: And I'm Leslie Segrete.
TOM: And while there’s plenty of sun abound right now, as the days start to get shorter, having a skylight is the best way to extend that daylight all year long.
LESLIE: Mm-hmm. And if you’ve ever dealt with a skylight, you know they can be a little bit on the tricky side, so we’ve got tips on the best type of skylights to install for long-term enjoyment. So we are welcoming Tom Silva  from TV’s This Old House , to talk about it.
TOM SILVA: Well, thank you for having me.
TOM: Hey, our pleasure. Now you are a guy that has put a lot of skylights  in over the years. Let’s start at the beginning. Where do you think the best place is to locate a skylight? And don’t say the roof. (Tom and Leslie chuckle)
TOM SILVA: (overlapping voices) Well, to locate the skylight – well, let me tell you first, by starting off, that I’ve got a few skylights in my house. I think I have 14.
TOM SILVA: Alright? So I know the ins and outs about skylights; living with them. And they do make a huge difference with natural light. If you place them on the south side of the house, you will get a tremendous amount of solar gain in the wintertime but that solar gain in the summer is not really a great friend.
TOM SILVA: So you want to put on filtered blinds to keep the heat out of that area.
TOM: Now, what about the glass for skylights, Tom? Is it important to have the very best, high-performance glass you can afford?
TOM SILVA: Absolutely. You want to have the best glass you can for two reasons: actually, to keep out that high heat that the sun can generate – it’ll actually cut down that radiant gain that you will get but it’ll also help with UV protection; and it’ll also hold that heat in, in the wintertime when you’re trying to heat up that space, or the cooling in, also in the summertime. So it does make a difference on the glass; always buy the best glass.
And if you want to place them on the south side and you’re worrying about the solar gain or too much heat in a –let’s say you’re in a part of the country that just has just too much sun, then they have sun glass that actually reflects the sun away and it really makes a big difference.
LESLIE: Now when it comes to selecting a skylight, does it really make a difference if you choose one that’s fixed versus one that’s operable or really a skylight is a skylight and that’s just secondary?
TOM SILVA: Well, I always think of a skylight as two different things. A lot of people call them "roof windows" or "skylights." A skylight, when I was growing up in the business, a skylight was a piece of glass that didn’t open. A roof window is a skylight that operates.
TOM SILVA: So if you want the venting capability – and they can make a tremendous amount of difference with venting – if you just crack that window, you get a negative pressure in the house right away and it makes a huge difference for getting heat out of the house.
TOM: What’s your experience been with the reliability of the venting controls, the electronic motors that operate those skylights that are way above your head? Do you find them to be dependable? Have you seen any problems with them?
TOM SILVA: When they first came out, I did have problems with them and I’m going back, oh, 20 years.
TOM: Yeah, well, you and I grew up in the same (chuckles) skylight school, so to speak.
TOM SILVA: (overlapping voices) Yeah, yeah. Yeah, yeah. I mean there were some issues.
TOM: (overlapping voices) And I was thinking the same thing.
TOM SILVA: Yeah, we actually – whenever I put a skylight that will open and close automatically, you want to make sure that you have a rain sensor on them and we actually …
TOM: Yeah. Oh, that’s a good point.
TOM SILVA: Yeah. Because if you’re not home and it starts to rain, you’ll get rain in your house. You want them to automatically shut. I remember the first skylights that we put in at least 20 years ago, there were probably about eight of them and they had rain sensors on them and the rain sensors malfunctioned. So it seemed like the only time they would open is when it was raining. (Leslie chuckles) But we had that problem fixed.
TOM: We’re talking to Tom Silva, from TV’s This Old House, for some tips on buying and installing a skylight.
So you mentioned rain. That’s the enemy. You want to keep that out of your house. What’s the best way to keep a skylight leak-free?
TOM SILVA: Well, flashing, flashing and flashing. Basically, paying attention to the way it is installed is very, very important. They have some great directions on these skylight boxes. Follow them.
And I always go a little bit further with the installation. I always take – and I think now they’re even in the directions but I always take a bitumen product, Bituthene, and I run it around the perimeter of the skylight after it is installed but before it is flashed. And I also make sure that the lower section of the bitumen is on top of the shingles at the bottom of the skylight.
TOM SILVA: And then that bitumen gets covered with flashing so it doesn’t break down from the ultraviolet light.
TOM: (overlapping voices) Got it. Follow the direction of the water and make sure that it is rolling appropriately down the shingles and over the flashing and not underneath.
TOM SILVA: Exactly. Exactly.
LESLIE: Tom, what do you think about sun tunnels? I mean they really offer the opportunity to have something like a skylight but when you don’t have the ideal roofing situation.
TOM SILVA: Well, a sun tunnel is great; you can get them in a couple of different sizes. I believe they’re in like a 14 and a 20 or a 22 or something like that. They bring in a lot of natural light during the day. They make a huge difference in hallways, closets; then you walk in and out of your closet during the day, you don’t want to have a light to have to turn on and off.
They’re great in offices, especially home offices, where you don’t have to run a light during the day. But it’s just that space that you may want to have a little bit of a light and they make a big difference. I believe the new ones even have lights in them.
TOM: Yeah. And they’re actually a lot easier to install, aren’t they?
TOM SILVA: Oh, tremendous. Yeah, I mean you cut a circle in a roof and slide your flashing up under.
TOM: (overlapping voices) And you’re done.
TOM SILVA: Lots of times, we bed the flashing into a mastic before we drop it in place.
TOM: (overlapping voices) Right. Well, good tips and lots of great options and, as I said in the introduction, the sun isn’t going to stay around forever, so now is a good time to think about adding a skylight so that you will have very bright spaces all year long.
Tom Silva from TV’s This Old House, thanks so much for stopping by The Money Pit.
TOM SILVA: It is my pleasure.
LESLIE: Well, to catch more of Tom and the entire This Old House team, including information on the current project, visit ThisOldHouse.com.
TOM: And This Old House is brought to you by The Home Depot. The Home Depot – more saving, more doing.