How much does a sliding glass door cost to replace?
Typical ranges, repair vs. replace, and what to look for in a new patio door.

Short answer: yes, a radiant barrier can help in Texas, but it's a supplement to attic insulation, not a replacement for it. The U.S. Department of Energy says radiant barriers work best in hot, sunny climates, and that some studies show cooling cost savings of about 5% to 10%. They help most when your ductwork runs through the attic.
A radiant barrier is a reflective material, usually aluminum foil bonded to a backing, installed in the attic to reflect the sun's radiant heat back toward the roof. Insulation works differently: it slows heat moving through materials. A radiant barrier reflects heat instead of absorbing it.
Our long, sunny summers are where radiant barriers do the most good. DOE notes they're more effective in hot climates than cool ones, and more valuable when there are ducts in the attic. The barrier keeps the attic air and surfaces around those ducts cooler.
For most DFW homes, air sealing and bringing attic insulation up to the recommended R-49 comes first. That's what keeps heat out of your living space. A radiant barrier is a good next step for homes with attic ductwork or a very hot attic. How much attic insulation you need
Enter your square footage, windows and doors for a quick, broad estimate.
In North Texas, a radiant barrier is worth considering, especially with ducts in the attic. Seal and insulate first, then add a radiant barrier for the extra edge. Comparing your options? Read spray foam vs. blown-in, or see how we handle attics.
Sources: U.S. Department of Energy, Energy Saver: radiant barriers; ENERGY STAR, recommended home insulation R-values.
Typical ranges, repair vs. replace, and what to look for in a new patio door.
Typical per-window and whole-house ranges, what drives the price, and how to compare quotes.
The usual culprits, from the attic to the ductwork, and which fixes actually work.