Dear Jim: I want to get the most efficient, easy-to-clean vinyl replacement windows. I am not sure whether to get them from a local manufacturer or a major national one. What design features should I look for? – Gary J.

Dear Gary: There are many local and regional vinyl replacement window manufacturers throughout the country. Many of them make quality windows equivalent to the national manufacturers, but not all do. The vinyl replacement windows I installed in my own home are from a local company.

There is great variation in the quality of vinyl windows, and price is not the best indicator. Compare the thickness of the frame wall, corner assembly method, interior frame insulation, type of spacer, and security. Also, when dealing with a local company, check references and how long it has been in business. A lifetime warranty is only as good as the company.

Since you are looking for easy-to-clean windows, tilt-in double-hung ones are your best choice. They are not quite as energy-efficient as casement windows, but casements can be a chore to clean yourself. Sliding windows are also fairly easy to clean because you can lift out the movable sash.

When comparing various vinyl windows, look at a sample cross-section of the frame and ask about the vinyl thickness. Greater thickness and more interior webs are indications of better quality. For large vinyl windows, interior metal reinforcing rods are often used to increase frame rigidity.

Make sure the window sashes have welded corners and are not just screwed together. They are generally thermally welded with heat. With the natural expansion and contraction of vinyl with temperature changes, screwed corners may become loose. Welded corners in the window frame are a plus, but because the frame is screwed into the wall, they are not as important.

Some vinyl windows, such as mine, have insulating foam inside the frame. Some companies inject polyurethane foam (best method) and others slip rigid polystyrene (similar to coolers) inside the frame. This does increase the efficiency somewhat and makes the frame stiffer. With all the interior webs and dead air spaces, even a hollow vinyl frame is a fairly good insulator.

Look for an insulating spacer (warm edge technology) between the panes of glass. The major manufacturers usually use rigid spacers for automated production and local manufacturers often use a flexible swiggle strip. My windows have swiggle strips and none has fogged up in more than 10 years.

Check the latches on the sashes. Double latches increase security and lock the sashes closed squarely against the weatherstripping. Pop-out stops add security by allowing the windows to open only a few inches for ventilation.

Write for (instantly download – www.dulley.com) Update Bulletin No. 700 – buyer’s guide of 15 high-quality, efficient vinyl window manufacturers listing frame-glass options, insulation type, styles, colors, features and a glass selector chart. Include $3 and a business-size SASE, and send to James Dulley, 6906 Royalgreen Drive, Cincinnati, OH 45244.