Do Motorized Shades Actually Cut Cooling Costs in Tucson?

Yes — but the honest version of that answer has conditions attached, and anyone who quotes you a percentage without seeing your house is making it up.

The physics is not in question

Solar radiation that comes through glass turns into heat inside the room. Once it is inside, the only way to remove it is to run the air conditioning, which costs money. Stopping it at the glass costs nothing to run.

That is the whole argument, and it is why shading is a more effective intervention in Tucson than in almost any market in the country. A west-facing wall of glass in the Catalina Foothills is beautiful at seven in the evening and brutal at four in the afternoon.

Why the savings number varies so much

Four things determine how much you actually save, and they differ enormously house to house:

• Glazing area and orientation. West and south glass is where the money is. North-facing glass barely matters.
• Existing glass performance. A house with modern low-E dual pane already rejects a lot of what an older single-pane house lets straight in.
• Shading fabric openness. A 3% openness solar screen rejects far more heat than a 10% one — and gives you less view. That trade-off is a real decision, not a detail.
• Your habits. Manual shades save nothing on the afternoons nobody closes them, which in practice is most afternoons.

That last point is the actual argument for motorisation, and it is worth being blunt about: the shades are not what saves you money. The schedule is.

Scheduling is the whole trick

Shades on an automated schedule close before the sun hits the glass, not after the room is already hot. That is the difference between preventing a cooling load and reacting to one, and it is the reason we set shades on astronomic timing — the system knows sunrise and sunset for your latitude and adjusts through the year, so the shades track the season without anyone resetting a timer in October.

On a well-configured system, the west-facing great room shades drop at a time computed from the sun's actual position, the HVAC never has to fight a spike, and you open them again in the evening for the view you paid for.

The second reason people buy them here

Fade. Arizona sun destroys upholstery, rugs, artwork and hardwood, and it does it faster than owners expect. We have been called to homes where a rug has two distinctly different colours either side of a line the afternoon sun draws across the floor.

Solar screens on a schedule protect the room during the hours nobody is in it, then open for the evening. For a client with significant furnishings or art, this justifies the system on its own, independent of any utility saving.

What we recommend, practically

• Prioritise west and south glass. Do those first. North-facing rooms can wait indefinitely.
• Quote shading and lighting control together. They share infrastructure and control surfaces, and doing both at once is cheaper than doing them a year apart.
• Hardwire the big ones. Battery shades retrofit beautifully into finished homes with no wiring, and on a normal schedule the batteries last a year or more. But on large, heavy shades or high-cycle rooms, hardwiring saves you a recurring annoyance. We will say which is which at the quote rather than after.
• Solar screens for view rooms, blackout for bedrooms and theaters. Different jobs, different fabric.

What we will not tell you

We will not give you a savings percentage before seeing your glazing, orientation and glass type. Anyone who does is guessing, and if the guess is wrong you will find out on a July bill rather than at the quote.

What we will do is walk your house free of charge, identify which glass is actually costing you money, and design the shading and schedule to target those hours. Read more about motorised shades, or request a free consultation.