INSULATION MARKETPLACE - 24" x10ft DIY Foam Core Reflective Insulation Sheet, Window Insulation Kit, Garage Door Insulation, Thermal Insulation Shield, RV Window Insulation + 35 Self Adhesive Pads

I have used these to block the windows to the bedroom where my wife often needs to sleep during the day, and it effectively blocks out 100% of the light. They also keep the room nice and cool in hot weather, and I'm assuming they will help retain heat in the winter just as effectively. Simple to cut and install; I used aluminum duct tape to seal the edges to ensure no seams to allow light/heat to seep through.

I ordered too short, so it didn't end up covering the entire window. I didn't want to mess it up around my portable ac unit exhaust, but it does block light and immediately I can notice it's a touch cooler in my living room. the adhesive stickers do not stay though, and it's in danger of falling until I can get more velcro strips. Debating if I want to buy another sheet or try to return this for a different oneUpdate: the seller reached out to offer me a refund without needing to return the item. Adding another star for their quick customer service. I'll still need heavier velcro, but I'll order another sheet to cover the rest of my window

I'm using this in my garage and it was easy to install. It's very thin and easy to cut/trim to customize for your space. It has a fairly reflective surface and does help insulate from the summer sun when placed over windows. I would recommend for small insulation projects.

Over the winter, I applied this to a couple of windows (laundry room and pantry) in my house and it cut down the draft tremendously. Easy to install. Easy to cut if need be. And the price is very reasonable. This is great to have on hand for house, RV or car. I don't think it's thick enough to help much insulating a garage door, however. But I live in an area that gets extreme cold winter temps. In a milder climate, it should be fine.

I bought this thinking the back would peel off like contact paper to stick to the surface. Instead, I was sent a sheet of these cheap little adhesive dots. So, I ended up having a place an order for double-sided tape. So, take the bargain price for this item and add on $6 for double-sided tape and you have a better true cost.

Not a fan. You can't get this to straighten out and it doesn't stick. Not happy with it.

I am using these on my CR-V to make custom shades for the side and back windows of my car for camping. I want something that I can use to block out the sun and other ambient light, and to help with keeping the car cool and also private at the same time.These are easy to cut to shape, and since they are super light, are easy to stick to just about everything. They work wonderfully for my purpose.

This insulation is thinner than what I usually prefer. I think a thicker insulation is better in a colder climate. We had some wind chills well below zero in January this year. I do think the reflective cover helps.