Record Lows in Houston! – Replacement Windows Help Keep the Cold Out

The latest storm that has dipped down into the deep south is named Ion. And, man is it a cold one. Here in Houston, it reached down into the mid 20’s and might even be colder tomorrow! This screenshot was taken at about 1:30pm…at almost the warmest part of the day.

double pane windows insulation from cold

Screen Shot Credit: Houston Chronicle 1/6/2014


Brrrrr. It makes me shiver just looking at temps that low. Now, go stand near your windows. Do you feel a draft? There are basically 3 ways that your old windows can and do make your home colder.

  • Improper Fit Our homes settle over time. The window and door openings become out of square (if they ever were square) and air leaks develop.
  • Poor Insulating Frame Those original aluminum frames without an insulating break are transferring cold.
  • Poor Insulation from Glass Single pane glass is a horrible insulator.

Your Original Windows are Inefficient Insulators

When your builder built your home, he basically had to comply with local building code as well as save cost to maximize profit. Home building is not a real high margin business. Until recently, all new windows were single pane, single strength glass and the frames were simple extruded or even roll formed aluminum. The exterior frame and the interior frame were really one extrusion. They were held together with screws in the corners.

Single pane glass was glazed into the frames with a little bit of rubber or silicon based gasket to “insulate” the glass from the frame material. How did that work out? Horribly!

The original windows were not efficient to begin with but now that they are 10 years or more old, they are getting worse. Mostly, because your home is settling (don’t worry, it’s normal) and your windows are starting to have little gaps around them. Gaps that let the cold air in and the warm air out! All that gas and electricity you are spending your hard earned dollars for trying to heat your home is just going out the windows.

Windows constructed with a single extruded aluminum molding allows temperature transfer between the outside and inside air. This means that when the frames get hot on the outside from the sun, the heat transfers to the inside and radiates off the interior surface. In cold weather, the frames get cold and then the warmer air inside causes the window to sweat. You’ll get condensation on the interior glass when they sweat.

The Science of Double Pane Windows as Insulators

When windows include two panes of glass, there are a couple of manufacturing changes in the way the window is constructed. First of all there is a spacer that is used between the panes of glass. This is the “gasket” that resides between the panes and creates the air gap. The spacer is usually rubber or urethane (both excellent insulators) and eliminate the heat and cold transfer between interior facing glass and exterior facing glass.

The air gap itself is important and quality windows have between ¾" or 7/8" and up to one inch. This is an effective insulating feature but is made much better when you fill that air gap with a heavier than air gas like argon gas. A nice wide air gap with argon and a great spacer combination provides an excellent insulated window.

Improvements in Replacement Window Frames

The final manufacturing piece of the puzzle is the frame. Modern replacement windows are constructed of virgin vinyl extrusions with welded corners. There are internal channels built into the extrusions that build up the rigidity and increase the insulating factor.

What’s the Final Piece of the Replacement Window Decision?

Finally, installation makes a big difference in the way that your new windows will perform. Houston Window Experts will custom measure each opening and custom order a window for each specific opening. This is important because, remember, your home has settled and the framing is not square anymore.

The “big box stores” have some cheap windows in stock. Stock windows were made square (meaning the corner angles are 90°) plus are usually in whole or half inch increments only. These will not do! On these stock windows the contractor will be shimming and filling the gaps with putty and wood. Or chopping the frame up with a sawzall.

Houston Window Experts will order your replacement windows much more precisely. Jeff and his crew will achieve a nice tight fit requiring only caulking. Now sawing, shims or putty.

Houston Replacement Windows Final Result

Tight, correctly measured windows that insulate against these arctic air blasts Houston is known for this time of year.