421 window installers ranked by CR ScoreUpdated 0 paid placements in this rankingHow we rank →
Best overall in Frederick: Quality Window & Glass Repair LLC, CR Score 91/100; 5.0★ from 392 Google reviews; open 24/7.
Best for emergencies (open 24/7): Safety Glass Repair, posts 24/7 hours; ranked #2 of 421.
Most-reviewed: American Home Contractors, 3,700 Google reviews at 4.9★, the most of 421 ranked; ranked #11.
Rankings can't be bought. Contractors can't pay to change their rank or score. How we rank
421 Frederick window installers are ranked here by CR Score, from 8 published factors. 67 are open 24/7, 276 open Saturdays and 152 open Sundays, based on posted hours. The median Google rating is 4.9★ across 421 rated businesses.
| Rank | Business | CR Score | Google rating | Based in | Hours | Best for |
|---|---|---|---|---|---|---|
| 1 | Quality Window & Glass Repair LLC | 91 | 5.0★ (392) | Germantown, 18 mi away | 24/7 | Overall |
| 2 | Safety Glass Repair | 88 | 5.0★ (165) | Gaithersburg, 21 mi away | 24/7 | Emergencies |
| 3 | Kennedy Locksmith | 88 | 4.9★ (980) | Aspen Hill, 37 mi away | 24/7 | — |
| 4 | Semper West Roofing | 86 | 5.0★ (303) | Frederick | 24/7 | — |
| 5 | Zen Windows Washington DC | 86 | 5.0★ (119) | Washington, D.C., 30 mi away | 24/7 | — |
| 6 | Auto Glass Experts | 86 | 5.0★ (50) | Aspen Hill, 22 mi away | 24/7 | — |
| 7 | Renewal by Andersen of the Capital Region | 86 | 4.9★ (1,041) | North Bethesda, 30 mi away | Sat · Sun | — |
| 8 | TEO Roofing | 85 | 4.9★ (283) | Frederick | 24/7 | — |
| 9 | Mid-Atlantic Home Improvement Co. | 85 | 4.8★ (45) | Gaithersburg, 21 mi away | 24/7 | — |
| 10 | KELEMER BROTHERS REPLACEMENT WINDOWS | 85 | 5.0★ (416) | Silver Spring, 34 mi away | Sat · Sun · Evenings | — |
Ordered by CR Score, a 0–100 score from 8 published factors. Paid placement never changes the order.
Ranked #1 because of its Google rating and availability: 5.0★ from 392 Google reviews, open 24/7.
Based on 6 of 8 factors; credentials and recency not yet collected.
Based in Gaithersburg, 21 mi away
Ranked #2 because of its Google rating and availability: 5.0★ from 165 Google reviews, open 24/7.
Based on 6 of 8 factors; credentials and recency not yet collected.
Based in Aspen Hill, 37 mi away
Ranked #3 because of its Google rating and availability: 4.9★ from 980 Google reviews, open 24/7.
Based on 6 of 8 factors; credentials and recency not yet collected.
Based in Frederick
Ranked #4 because of its Google rating and availability: 5.0★ from 303 Google reviews, open 24/7.
Based on 6 of 8 factors; credentials and recency not yet collected.
Based in Washington, D.C., 30 mi away
Ranked #5 because of its Google rating and availability: 5.0★ from 119 Google reviews, open 24/7.
Based on 6 of 8 factors; credentials and recency not yet collected.
Based in Aspen Hill, 22 mi away
Ranked #6 because of its Google rating and availability: 5.0★ from 50 Google reviews, open 24/7.
Based on 6 of 8 factors; credentials and recency not yet collected.
Based in North Bethesda, 30 mi away
Ranked #7 because of its Google rating and trade focus: 4.9★ from 1,041 Google reviews, listed on Google as “Window installation service”.
Based on 6 of 8 factors; credentials and recency not yet collected.
Based in Frederick
Ranked #8 because of its Google rating and availability: 4.9★ from 283 Google reviews, open 24/7.
Based on 6 of 8 factors; credentials and recency not yet collected.
Based in Gaithersburg, 21 mi away
Ranked #9 because of its Google rating and availability: 4.8★ from 45 Google reviews, open 24/7.
Based on 6 of 8 factors; credentials and recency not yet collected.
Based in Silver Spring, 34 mi away
Ranked #10 because of its Google rating and trade focus: 5.0★ from 416 Google reviews, listed on Google as “Window installation service”.
Based on 6 of 8 factors; credentials and recency not yet collected.
Based in Washington, D.C., 32 mi away
Ranked #11 because of its Google rating and review volume: 4.9★ from 3,700 Google reviews, the most Google reviews on this list (3,700).
Based on 6 of 8 factors; credentials and recency not yet collected.
Based in Catonsville, 39 mi away
Ranked #12 because of its Google rating and availability: 5.0★ from 97 Google reviews, open 24/7.
Based on 6 of 8 factors; credentials and recency not yet collected.
Based in Damascus, 12 mi away
Ranked #13 because of its Google rating and availability: 5.0★ from 263 Google reviews, open 24/7.
Based on 6 of 8 factors; credentials and recency not yet collected.
Based in Darnestown, 27 mi away
Ranked #14 because of its Google rating and trade focus: 4.9★ from 231 Google reviews, listed on Google as “Window installation service”.
Based on 6 of 8 factors; credentials and recency not yet collected.
Based in Chantilly, 36 mi away
Ranked #15 because of its Google rating and availability: 4.9★ from 2,385 Google reviews, open 24/7.
Based on 6 of 8 factors; credentials and recency not yet collected.
Based in College Park, 37 mi away
Ranked #16 because of its Google rating and availability: 4.8★ from 159 Google reviews, open 24/7.
Based on 6 of 8 factors; credentials and recency not yet collected.
Based in Merrifield, 31 mi away
Ranked #17 because of its Google rating and availability: 5.0★ from 24 Google reviews, open 24/7.
Based on 6 of 8 factors; credentials and recency not yet collected.
Based in Frederick
Ranked #18 because of its Google rating and availability: 5.0★ from 46 Google reviews, open 24/7.
Based on 6 of 8 factors; credentials and recency not yet collected.
Based in Fairfax, 38 mi away
Ranked #19 because of its Google rating and trade focus: 4.8★ from 669 Google reviews, listed on Google as “Window installation service”.
Based on 5 of 8 factors; credentials, recency and availability not yet collected.
Based in Gaithersburg, 22 mi away
Ranked #20 because of its Google rating and availability: 4.9★ from 401 Google reviews, open 24/7.
Based on 6 of 8 factors; credentials and recency not yet collected.
Based in Falls Church, 40 mi away
Ranked #21 because of its Google rating and availability: 4.8★ from 50 Google reviews, open 24/7.
Based on 6 of 8 factors; credentials and recency not yet collected.
Based in Ballenger Creek, 6 mi away
Ranked #22 because of its Google rating and availability: 4.8★ from 93 Google reviews, open 24/7.
Based on 6 of 8 factors; credentials and recency not yet collected.
Based in Germantown, 18 mi away
Ranked #23 because of its Google rating and trade focus: 5.0★ from 212 Google reviews, listed on Google as “Window installation service”.
Based on 6 of 8 factors; credentials and recency not yet collected.
Based in Columbia, 31 mi away
Ranked #24 because of its Google rating and trade focus: 4.9★ from 99 Google reviews, listed on Google as “Window installation service”.
Based on 6 of 8 factors; credentials and recency not yet collected.
Based in Frederick
Ranked #25 because of its Google rating and trade focus: 5.0★ from 29 Google reviews, listed on Google as “Window installation service”.
Based on 6 of 8 factors; credentials and recency not yet collected.
#1 to #25 are shown in full above. Here are #26 to #50, in CR Score order; each links to its profile. We publish the top 50 of 421 ranked window installers here; the rest are on their profiles.
20 more window installers within 40 mi that we can't rank yet: too few reviews, or a trade we couldn't confirm. Listed A to Z.
Typical prices in USD, adjusted for Maryland with a published regional index. Each row names its basis and month.
| Job | Low | Typical | High | Basis | Checked |
|---|---|---|---|---|---|
| Window replacement | $3,370 | $7,200 | $11,600 | Per project (several windows): typical range of customer-reported projects. US national range × 0.98 South Atlantic factor (2025 Cost vs. Value Report) | October 2026 |
We scored 421 Frederick window installers on 8 factors, weighted as shown. A business is ranked when its trade is confirmed and it has 3 or more Google reviews or a claimed profile. Unknown factors are left out of the score, not counted as zero. Scores last refreshed October 22, 2026.
Paid placement never changes a rank or score. Featured businesses are paid, labelled, limited to 3 and shown above the ranking, outside it.
| Factor | Weight | Computed from | In Frederick data |
|---|---|---|---|
| Reputation | 35% | Bayesian-adjusted Google star rating | Measured |
| Credentials | 15% | Active state license 0.6, bond 0.2, workers’ comp 0.2 | Not yet collected |
| Review volume | 10% | log10(reviews + 1) against the list maximum | Measured |
| Recency | 10% | Share of reviews from the last 12 months | Not yet collected |
| Availability | 10% | Weekly open hours, Saturday, Sunday, 24/7 or same-day | Measured |
| Trade focus | 10% | Google main category 1.0, business name 0.7, additional category 0.5 | Measured |
| Proximity | 5% | 1.0 when based in the city, falling to 0 at the trade’s radius | Measured |
| Completeness | 5% | Website, photos, description, hours, claimed profile (0.2 each) | Measured |