Do I need to cover PEX for UV light in crawl space?

[Brad Littlejohn]

I am in installing Pex-b in the house. I have lights in the crawl space, to work on vapor barrier, duct work and etc.... Do I need to cover pex with a UV protector? The Pex I have says that it has 6 months of UV protection. Does that mean 6 months of direct sunlight over the course of the Pex's lifespan? Or when installing, you have six months to complete the job, then after that you much make sure that pex is not exposed to UV light.

 

[Reach4]

I have lights in the crawl space, to work on vapor barrier, duct work and etc.... Do I need to cover pex with a UV protector?

Any artificial light you put in the crawlspace will have little to no UV.

Yes, white LEDs work by generating UV and phosphors convert to visible light. But the UV leakage is small.

No worries about your artificial lights IMO, as long as you don't use mercury lights.

 

[Sponsor]

 

[Brad Littlejohn]

Ok cool. Thanks for the advise. Doing a poly B to pex for the whole house and want to do it right.

 

[Jadnashua]

It's not a bad idea to insulate the pipe, especially on the hot lines, and that would also protect them from any UV. Depending on the design of the crawl space, there may be some vents that could let some light in, but it likely would not be much.

 

[Brad Littlejohn]

It's not a bad idea to insulate the pipe, especially on the hot lines, and that would also protect them from any UV. Depending on the design of the crawl space, there may be some vents that could let some light in, but it likely would not be much.

Thank you. I have closed the vents and put in a vapor barrier.

 

[Jeff H Young]

Thank you. I have closed the vents and put in a vapor barrier.

Dont know if closing vents to crawl space a good idea ? never heard that to be a good idea

 

[wwhitney]

Dont know if closing vents to crawl space a good idea ? never heard that to be a good idea

There's two basic strategies to handling crawlspaces as far as moisture and temperature: either you put it outside your thermal and air envelope, or you put it inside your thermal and air envelope.

Outside is more common--you ventilate the crawl space so any ground source moisture can dissipate outside. But your crawl space temperature is comparable to the outside temperature, and you need to insulate your floor joists. Also, you should air seal the floor plane, but that's not often done.

Inside can perform better in some climates--you seal off the crawl space from the outside, including a vapor barrier over the ground. You insulate the crawl space walls instead of the floor joists. And you often provide a little conditioning of the space, e.g. a dedicated dehumidifier or a vent from the HVAC system.

Cheers, Wayne

 

[JohnCT]

Foam insulation sleeves are cheap. I'd put them on for giggles. Who knows, it might prevent rodent damage. FWIW, white LEDs put out more UV light than most people realize.

John

 

[Jeff H Young]

There's two basic strategies to handling crawlspaces as far as moisture and temperature: either you put it outside your thermal and air envelope, or you put it inside your thermal and air envelope.

Outside is more common--you ventilate the crawl space so any ground source moisture can dissipate outside. But your crawl space temperature is comparable to the outside temperature, and you need to insulate your floor joists. Also, you should air seal the floor plane, but that's not often done.

Inside can perform better in some climates--you seal off the crawl space from the outside, including a vapor barrier over the ground. You insulate the crawl space walls instead of the floor joists. And you often provide a little conditioning of the space, e.g. a dedicated dehumidifier or a vent from the HVAC system.

Cheers, Wayne

Thanks Wayne, I belive its a serious thing changing from one strategy to the other, something not to be taken lightly , Ie not something you just decide one day like I think ill just cover up all these vents . Probebly very well thought about by someone befor doing it