Do Cellular Shades Really Stop Drafts? A Straight Answer for Lawrence

Lawrence Window Treatments · 2026-10-13

Plenty of Lawrence homeowners blame a draft on a bad seal long before they consider that a window's cold glass, not moving air, might be the real source of a chilly room.

Why Older Windows Feel Colder Than the Thermostat Says

Here's the thing people get wrong most often: they assume a cold room means a leaky window, order weatherstripping, seal every gap they can find, and the room's still cold. That's because a big part of what you're feeling isn't moving air at all. It's radiant heat loss, your body cooling toward a cold surface, plus a convective loop where air against that cold glass sinks and rolls across the floor. Both happen on a window with a perfectly good seal.

Older glass in a lot of Lawrence homes makes this more obvious, since the surface temperature of single-pane or early double-pane glass runs colder than current glass on a cold night. The thermostat has no way to measure any of this. It just reads air temperature at one spot in the room, which is why two people standing in the same room can disagree about whether it's actually cold.

Mount Style and Fit Change How Much Draft Gets Through

Picture a bay window or a sliding glass door, common trouble spots for cold rooms, and it's easy to see why fit matters so much. An inside-mounted shade on a bay window leaves small gaps at each angle where the panes meet, and that's exactly where the cold air rolling off the glass finds its way past the shade and into the room.

Mounting the shade outside the frame instead, so it overlaps the wall or trim on all sides, closes off more of that path. It's a better fit for a drafty corner window or an old sliding door track that was never great at sealing to begin with. Side channels are worth asking about on these problem spots too. They run down the edges and close the last bit of gap a plain outside mount leaves open.

Layering Shades and Drapery for the Coldest Rooms

A single layer of cellular shade helps, but the coldest rooms in a house, usually the ones facing north or with a lot of glass like a sunroom or a bay window, often do better with a second layer. Drapery hung over a cellular shade adds another buffer of still air between the room and the window, and a lined panel does more work than an unlined one because the lining itself has some mass and slows air movement across the fabric.

For this to actually help rather than just look nice, the drapery needs to hang close enough to the wall and long enough to reach the floor or windowsill without a big gap underneath. A rod mounted 4 to 6 inches above the frame, with panels wide enough to stack off the glass when open and close fully over the whole opening at night, does more for comfort than a narrow panel that only covers the center third of the window.

How Cellular Shades Trap Air Instead of Just Blocking Light

Cellular shades get their name from the honeycomb-shaped cells the fabric folds into, and those cells are the entire point of the design. Each cell holds a pocket of still air, and still air resists heat transfer far better than moving air, which is why the shade acts as insulation rather than just a light filter.

Cell depth generally runs from 3/8 inch on the smallest profiles up to 1 inch on the largest, and shades are built as single-cell, one row of pockets, or double-cell, two rows stacked front to back. Manufacturer-published R-values usually fall in the range of R-1.5 to R-2 for single-cell fabric and R-3 to R-3.5 for double-cell, figures that describe the shade's own insulating contribution rather than a guaranteed change in a heating bill. Double-cell costs more and stacks a little thicker when raised, a tradeoff worth knowing before ordering a whole house of them.

Cell size also affects light control options somewhat independent of the R-value story. Room-darkening and blackout cell fabrics are available in both single and double-cell construction, if that matters more for a bedroom than the insulating value does.

What Window Treatments Can and Can't Fix

It's worth saying plainly: no shade or drapery, at any price, replaces a window with a genuinely failed seal or a warped frame. Weatherstripping and air sealing are a separate, usually less expensive project, and doing that first on the worst offenders sometimes changes what a room actually needs from its treatments afterward.

Full window replacement sits at the far end of the cost range and solves the glass problem directly, but it's a much bigger investment than treatments and not always necessary right away. For a lot of Lawrence homes, a combination, minor air sealing where it's cheap to do, then treatments sized to the room, covers the comfort problem without the largest expense on the list. It's worth pricing that combination out before jumping straight to the most expensive option on paper.

Walking through each cold room in the house with someone who measures windows for a living tends to turn up patterns you wouldn't catch alone, which is exactly what a free in-home measure is for.

Frequently Asked Questions

Will cellular shades stop a window from feeling drafty?

They'll reduce the radiant chill and the convective draft that come off cold glass, which is most of what people notice sitting near a window in winter. They won't stop an actual air leak from a failed seal or worn weatherstripping. That's a separate repair, worth checking for before assuming shades alone will solve a cold room.

What's the difference between single-cell and double-cell shades?

Single-cell fabric has one row of air pockets and double-cell has two, stacked front to back. Double-cell insulates somewhat better, generally in the R-3 to R-3.5 range compared to R-1.5 to R-2 for single-cell, but costs more and stacks a little thicker at the top when raised. For a genuinely cold room it's usually worth the difference.

Does mount style really make that much difference?

It can. Inside-mounted shades leave a small gap between the fabric and the frame on both sides, right where cold air rolling off the glass gets past the shade. Outside mount overlaps the frame instead, which usually closes off more of that path, especially on an older or slightly out-of-square window.