Costello Windows Reviews 

The installer was very friendly and walked me through everything on the day. The door was exactly what I wanted and looks great installed. The old door was taken away and the installer cleaned up everything after he was done, even cleaned the door.

I ordered two windows and a sliding door in June. At the time, I was given a lead time of 5 weeks for production and fitting. I agreed and paid a deposit-half the total cost. The 5 week timeline came and went without any contact from Costellos.
By the end of September, following weeks of phone calls and hounding, I finally got the windows fitted, following full payment of the remainder of the balance. I never once received an explanation for the delay or an apology.
The fitter did his best but the manufacture of the windows was absolutely shocking. Gaps in joints, miter joints filed, filled and forced to ‘fit’, sashes not sealing around the frames…the list was endless.
I called the fitting department to explain the issues and was told I would be called back (multiple times). I never was. Multiple calls were fobbed off and never returned. I finally got in contact with one employee that actually helped and they finally agreed to replace the window sashes. I would have preferred to replace the frames too but I was out of time with a plasterer booked. The replaced sashes weren’t much better but they’ll do.
Costellos really show how much they value their customers- in four months, I was contacted twice; once to request a deposit, once to request final payment. I could possibly overlook extremely poor customer service if the product had been decent but both were a massive disappointment.

The service was very good and the fitter of the new door was very thorough. Good quality service.

Professional team from the initial sales enquiry to the delivery and installation of windows and doors

Costello Windows provided beautifully designed and manufactured hybrid sash windows. They were a pleasure to deal with.

I am deeply disappointed and frustrated with the service provided by Costello Windows. I paid €4,000+ in full upfront, expecting a premium, professional experience. Instead, I have been left with structurally defective products, property damage, and a freezing home.
After a full month delay, the installation crew arrived severely late for two consecutive days, working into the night and forcing me to rearrange my personal and professional plans. Worse, the quality of the job is shocking:
1. Manufacturing Defect: The brand-new double-glazed window unit has permanent fog/opacity trapped inside the sealed glass panes. It is a complete factory failure.
2. Defective Seals: The internal black silicone is full of large air bubbles and gaps where it is already lifting away from the frame.
3. Incomplete External Fitting: The blue expanding insulation foam on the exterior has been left completely exposed to the elements without any perimeter silicone seal, leaving my house freezing cold.
4. Property Damage: The fitting crew severely scratched the dark PVC profile, leaving a deep, permanent white gouge.
5. Safety Issue: The crew left without giving me the security keys for the windows, meaning my ground-floor windows cannot even be locked.
I explicitly chose Costello Windows for the fitting because they previously penalized me for using independent contractors, promising their internal service would avoid issues. Instead, they used a third-party subcontractor (Bruno, completely unreliable), and now that the job is a disaster, management (Brendan, same exact work ethic) has gone completely silent and refuses to respond to my emails.
I have refused the final sign-off. Do not pay this company upfront; their customer service disappears the moment they have your money.

James fitted our front composite door and was very punctual and very tidy worker top class fitting job very thorough worker and professional.

Top class job done in Ballybunion. Installer did a fantastic job for us. Great work and fast. Can't remember the name, but he was a Duagh man! Door is great, cuts out all the draughts that were there and all for a really good price. Will be using Costello Windows again in the future.

Got new front door fitted.
From start to finish they gave good advice & recommendations to help us make the best choice.
The guy fitting the door was very good & friendly & helpful.

⭐⭐⭐⭐⭐ Excellent Service from Costello Windows and Doors

We recently had two new SEAI-spec uPVC doors installed by Costello Windows and Doors, replacing our existing Wooden and PVC doors, and we couldn’t be happier with the service.

The installer arrived ahead of schedule and was extremely professional, polite, and courteous throughout the job. He really went the extra mile to ensure everything was fitted perfectly, taking the time to double-check that both doors locked properly and that all the hinges and fittings were working exactly as they should.

He also left both installation areas clean and tidy, with everything looking great when he finished.

It’s refreshing to see such attention to detail and pride in workmanship. We’re delighted with our new uPVC doors and would highly recommend Costello Windows and Doors to anyone looking for quality products and excellent service.

From the first call to Brenda all the way thru, they were a pleasure to deal with. On the day of fitting arrived early, extremely professional and great housekeeping, miminum paint to be touched up.

From Hayden in Sales, Brendan in Service and Rafael and the fitters, everything has gone very smoothly with Costellos again. This is the second time we have used Costello's for windows. The first was four years ago and those windows have been perfect. We were delighted to use them again to fit the main house. Excellent quality, communication and service. Any previous follow-ups with Amelia have also been managed well. Thank you all!

Top class service from the initial call to installation. James the installer done a great job, lovely finish and left the place spotless after he was done. Were delighted with our new front door, would highly recommend 👍

"We had two beautiful composite doors installed last week and we couldn't be happier. James did an excellent job — such a hard worker, kept everything clean, and saw the job through perfectly from start to finish. The difference in warmth in our home is absolutely amazing already! The team were very accommodating with every request, and their showroom in Limerick is great — all the staff are knowledgeable and reliable. Best price guaranteed too — we highly recommend Costello Windows!"

Had new windows fitted and I couldn’t be happier. The fitters left no mess and were very courteous and polite. I would highly recommend Costello windows if anyone need new windows. A very satisfied customer. Thank you.

The fitter was professional,tidy experienced and friendly
Excellent job, Brillant service and quality work

Very happy with quality of door and service when fitted.

The two lads that fitted our windows were excellent, worked hard and late each day to ensure the job was completed on time. Very tidy, courteous and professional. Thank you for a great job. Brendan Waterford

New back door fitted by Costello Windows. Exactly what I asked for.. looks great. Fitter very clean and tidy. Definitely recommend

Large and awkward windows, installers were great and put in a couple if long days; few snags along the way but they resolved everything back at office; finished last pane on Saturday morning and left everything clean and tidy; was very pleased