[GTO]

We have some great posts on automotive sunfilm, so I wanted to create this one for home sunfilm.

The Man Cave in my house (my home office & home gym) faces the south-west direction. Has a powerful air-con and is totally cool up to 2 PM in the summer months. But once the sun goes toward the west, the afternoons are unbearable. On two sides of the man cave are big glass areas that I want to apply sunfilm on. Primary objective = keeping the room cooler in the afternoon.

Which sunfilm to install on the windows?

- Dark or transparent?

- Brand?

- Regular or reflective?

- Approx rate per sq ft?

Just spoke to my auto accessory guy and he inundated me with options! What better place to get this kind of practical advice than Team-BHP .

Thanks in advance.

[Newtown]

Originally Posted by GTO

But once the sun goes toward the west, the afternoons are unbearable. On two sides of the man cave are big glass areas that I want to apply sunfilm on. Primary objective = keeping the room cooler in the afternoon.

What level is this room located in your home?

About a year back, I insulated my ceilings with XPS sheets. Has made a world of a difference. For my tall windows, have double glazed glass and roller blinds.

[SmartCat]

Originally Posted by GTO

The Man Cave in my house my home office & home gym faces the south-west direction. Has a powerful air-con and is totally cool up to 2 PM in the summer months. But once the sun goes toward the west, the afternoons are unbearable. On two sides of the man cave are big glass areas that I want to apply sunfilm on. Primary objective = keeping the room cooler in the afternoon.

The heat radiation into the room via large windows is "temporary". Just closing the blinds will reduce the heat radiation.

I think it is the roof that is the problem. The afternoon sun heats up the roof and this heat is radiated into the room for many hours. Here in Mangalore (similar weather as Mumbai), many houses cover up the roof like this:



All the heat is absorbed the "top hat", and very little heat is transferred to the roof. As a bonus, heavy moonsoon rains do not cause leaky roof problems (because rain too is deflected away from the roof).

Another option is to apply a coating of "heat reflective roof paint". Not sure about its effectiveness though.

[GTO]

Guys, thanks for the suggestions. But please also answer the sunfilm queries on brand etc.

[Kosfactor]

Large glass windows = Green house effect

Direct sunlight be it on the roof or the side of the building or through large windows is going to cause discomfort.

It maybe impractical to shield the outer walls and roof, but windows are a bit easier - you can use Bamboo blinds on the outside + curtains on the inside to block the light when its very bright.

Edit : Use dark film of course, lesser light transmission is better. However it may completely block out your view in the night.

[Fuldagap]

Last year I got very large windows of my workplace installed with sunfilm. The place is west facing and after say 1100 hrs till sunset it gets direct sunlight so much so that all 4 ACs inside were basically ineffective.

To get the installation done I visited a lot of local vendors. Learnt a lot about sunfilms.
Also got in touch directly with 3M, Garware & V-KOOL offices. After collating all the quotations and technical specs, it was a branded sunfilm vs chinese sunfilm installation. If I had gone with a branded one, it would be 3M vs V-KOOL.

The quotations for the branded ones were more or less similar, 3M being the most expensive. All of them have the options for dark, translucent and reflective films, including the chinese ones. All of them also come (optionally) with some kind of coating (forgot the term) at an additional price, which prevents weathering of the film and looks neater than a normal one.

Also learnt that a vendor could cheat and install a chinese one and price it for a branded one. There is no way to ascertain it, unless the 3M, Garware or V-KOOL do it themselves.

A sunfilm could be installed easily as a DIY. Purchase a roll after gathering the required footage and install it yourself. Basic tools are required along with some solution to first clean and wipe the glasses. Like they do for car glasses.

Finally, I went for the cheapest chinese one, 100% dark (as claimed by the vendor). Bought a roll very cheap, took the required tools and the cleaning solution from the vendor (returned after usage) and installed it myself with help from staff. The final outcome was not as professional with some bubbles here and there between the film and the glass.

The film is dark enough and during the day nobody can see from outside the indoors. It successfully prevents heat and the ACs work flawlessly now. If it were for office or home, I would have definitely gone for 3M/V-KOOL.

For home, I'd recommend getting it done professionally directly from the OEM guys. It will be a tad expensive but totally worth it. They would also visit the home and suggest properly which film to go with. Rest is upto you to decide which would get the job done and which would look better on those windows, from outside and inside.

The pricing difference between the chinese ones and the branded ones was in the ratio 1:7. The branded ones are totally worth it for years of peace of mind.

The vendors quoted me a charge (for the chinese ones) of roll price and the labour in the ratio of 1:3.

My suggestion: go for a branded one and get it installed by the OEM guys. Unless you have a trustworthy vendor.

[Sheel]

If the place gets too warm, I doubt, the sunfilms will do the job. There is no harm in getting a quote / estimate from reputed UPVC company (Fenesta / Veka / Kommerling / Prominence, unsure of other reputed brands) with 2 or 3 glasses (DGU or triple glazed unit) which will block the heat.

UPVC installation won't be tedious or much messy, it's a one day job. Get the estimate, they will get it prepared in approx a month and should be installed by one day. You may try this option. I got my entire house done with UPVC in double glazed unit. During that time triple glazed units were not available or I was aware of. You may try this. Keeps all heat, noise outside. Try getting a quote .

[neofromcapone]

Originally Posted by GTO

Guys, thanks for the suggestions. But please also answer the sunfilm queries on brand etc.

V-Kool.

In the 90's I used to work in the Vile Parle outlet.
If you use the clear film (installed on the windscreen of the car), IIRC it will cut ~90% sunlight heat.
For the glare, you can use white, off-white curtains (just realized it's a man-cave) But you can use some other method blinds or rattan curtains.

This way you cut out the heat and enjoy the view.


Hope this helps.

[sagarpadaki]

Originally Posted by GTO

Guys, thanks for the suggestions. But please also answer the sunfilm queries on brand etc.

Garware has architectural sun films specifically for home applications. You may check them out.

https://garwaresuncontrol.com/my-window-film/

[NomadSK]

I’m not sure about the architecture of your home unit. But if the heat is being radiated from the exposed walls to the sun, you will need to insulate them. We have here thermocole layer above the false ceiling attached to the inside of the roof, which insulates it.

However, if the concern of heat transmitting is only through windows, then I would suggest vacuum insulated glass, all our offices have such double walled glazing. Summers outside temperature reaching Upto 50C and inside it’s pretty cool. It consist of two single panes sealed with vacuum space between them. With there nothing between the glass, there is nothing to transfer the heat between the panes and the room would stay at cooler optimum temperature, also acts as a good sound insulator, if you stay nearby a high traffic road. I’m not sure, but I guess windows can be replaced without the need for additional structural work being undertaken, on the same frame.

PS - I don’t have an idea about the costing.

@Smartcat - the shed over the roof would require structural engineering to install considering the wind load as the surface area is huge. And even the dead load of the structure. In my opinion it can’t be done without proper designing, specially if you live near coastal high windy areas and probably will cost a lot.

[Fuldagap]

Originally Posted by NomadSK

I’m not sure about the architecture of your home unit. But if the heat is being radiated from the exposed walls to the sun, you will need to insulate them. We have here thermocole layer above the false ceiling attached to the inside of the roof, which insulates it.

With there nothing between the glass, there is nothing to transfer the heat between the panes and the room would stay at cooler optimum temperature, also acts as a good sound insulator, if you stay nearby a high traffic road. I’m not sure, but I guess windows can be replaced without the need for additional structural work being undertaken, on the same frame.

This indeed is as excellent as it gets. Watching the traffic "on mute" feels lavish to the core. This is much better than installing a film; the film, however costly, takes away the basic function of a transparent glass window, that too permanently. The double glass vacuum windows are chic.

[MT_Hyderabad]

Heat protection: Which sunfilm for large windows at home?
Answer: Curtains

In a home/office set up, curtain works best. Not the cloth ones alone, but retractable or roller blinds also.

Get one of those and enjoy all weathers. Sunfilms are too binding. I will only use them on kitchen windows, where the burner is somewhat (not very) close to the window, which becomes a fire hazard.

If cost is not a problem, one can also go for motorized blinds. I have only seen them in offices, don't have any personal experience.

[Comrade]

You can try 3M Prestige Series. Supposed to be top of the line and costs around Rs 350 per sft (last I checked). I am sure there will be similar products from other manufacturers. These are films with 50-70% visibility (70% visibility is almost as good as clear glass if sunlight is direct) while cutting down the IR rays.

Next better option is to replace glass with Low-E glass (single pane) like Saint Gobain Antelio Plus or Cool-Lite. Visibility reduces to 20-60% (depending on the glass chosen) but cooling efficiency is much better than sun-films.

Next better option is to replace the window with Double Glazed Unit (two panes of clear glass with inert gas like Argon filled in the middle). Visibility is same as clear glass but cost will be high.

Best option is to replace the window with Double Glazed Unit that has Low-E glass as outer pane and clear glass as inner pane. Visibility reduces to 20-60% but cooling efficiency is best and cost is highest.

[niteshbids]

The options of changing windows and installing blinds/curtains are both great suggestions.

However, blinds may not work in case you want to retain the view.

Changing the windows to energy efficient upvc windows would be an optimum solution but the amount of work needed would depend on the type of windows or glass installed currently. If the glass is framed in wood or iron, then civil work may be involved which would be a lot of disturbance. If it is in aluminium frame, upvc frame or frameless installation, then the change would be easier.

But in any scenario, I would recommend replacing the glass with sun control glass options than putting a film. For the easiest option, you can chose a similar thickness glass which would be the easiest, and if the frame permits, a DGU as Sheel mentioned earlier.

Selection of glass should be based on various factors such as desired glass colour, the light transmission percentage that you'd want, the internal reflection, colour rendering index, SHGC and U value.

Typically you'd want high values for light transmission and CRI while going as low as possible for internal reflection, SHGC and I value.

Some examples of the said data from saint gobain catalogue is attached.

[Brumby]

The best option would be to go for vacuum sealed double glazed tinted glass with dark curtains.

Tinted glass is available in various colours as well.

I had a similar situation with living room and two bedrooms of my flat facing west. I used films but eventually the film developed scratches and started to peel off.

At the time of renovation, I renewed the windows with double glazed tinted glass and dark curtains and that made a lot of difference.

The solution for what ever heat is absorbed by the structure will require more expensive and time consuming approach.

Cheers