Pontrug is part of Llanrug community, so this is the area closest to home. Most houses here are stone and slate cottages, terraces built for quarry workers, and newer family homes. Here is what each kind of job looks like around Llanberis and Llanrug.
House extensions in Llanberis and Llanrug
Around Llanrug and Cwm-y-glo, replacing an old conservatory with a solid, insulated room you can use all year is a popular job – the mountain weather makes a cold conservatory hard to live with.
In Llanberis, check first whether your address is inside Eryri National Park. Inside the Park, planning is decided by the Eryri National Park Authority, and the rules for extensions are stricter.
New homes in these villages often sit on sloping plots, with stone walls and old drains to work around.
Every new home needs sprinklers and usually SAB approval. Near Llanberis, the National Park and the Dinorwig slate World Heritage Site can affect what is allowed.
Garages on the newer homes in Llanrug and Llanberis make good home offices and spare bedrooms.
If the garage is attached and the work is inside, planning permission is usually not needed outside the National Park. Building Regulations approval is.
Cottage renovations are a big part of building work around here. Old stone and slate houses have walls that move, floors that aren't level and surprises behind the plaster.
We look at the walls, roof and damp first, then plan the work around what we find, and explain the options when something unexpected turns up.
This part of Gwynedd sits right on the edge of protected land, so check your address early:
Eryri National Park: some addresses around Llanberis come under the Eryri National Park Authority for planning, others under Gwynedd Council. The rules for extensions are stricter inside the Park.
The slate World Heritage Site: the Dinorwig quarry landscape above Llanberis has been part of the "Slate Landscape of Northwest Wales" World Heritage Site since 2021. Outside changes near it may get extra attention.
Outside the Park and the World Heritage Site, the normal Welsh permitted development rules usually apply. See our guide to extension rules in Wales.
Holiday lets
Planning permission is needed before a main home becomes a second home or short-term holiday let: in Gwynedd Council's area since 1 September 2024, and in Eryri since 1 June 2025.
Old quarry cottages
We look at the walls, roof and damp first, then plan the work around what we find.
Reviews
Don't take our word for it
Real words from real customers in Gwynedd, Bangor and Anglesey.
“Once the decision to FINALLY get a new kitchen was made the nerves set in. There was no need, Gavin and his team made everything right. Communication was excellent … And best of all done within timescale agreed. Very Happy.”
★★★★★
Office repairs · Google
“I’ve used Gwynedd Construction on several occasions for general repairs in my office, and every time the service has been exceptional. Gavin, the owner, is professional, reliable, and clearly takes pride in the work his team delivers. … Highly recommended if you’re looking for quality workmanship in North Wales.”
★★★★★
Garage conversion
“Can't speak highly enough of Gwynedd Construction Ltd. They completed the work on time and to an extremely high standard. Nothing was too much trouble … Will definitely use them again.”
★★★★★
Building project · Google
“I must commend the excellent high-quality construction work that was delivered. … The planning phase was executed to perfection … the team's ability to effectively manage unexpected changes truly stood out. … 100% recommend.”
★★★★★
Bedroom work · Google
“Gwynedd Construction did an excellent job on the work i had done on my bedroom. They were very professional and polite. They cleaned up afterwards and you wouldn't have known they had done work on my bedroom.”
★★★★★
Walls removed, 3 RSJs fitted
“Gavin and Geraint were extremely professional from our very first meeting. They are two hard working, trustworthy, reliable and extremely tidy workmen. … Can't recommend them highly enough.”
★★★★★
Renovation project · Google
“Can't speak highly enough of Gwynedd Construction and the incredible work they did on our one-year renovation project. … What impressed us most was their ability to handle unexpected challenges with ease, offering creative solutions while staying on schedule and within budget.”
★★★★★
Extension, garage & patio · Google
“The team built a large extension at the back of my property and a detached garage … I then had the team back to do a patio and a retaining wall. Also very clean and tidy workers … Good job Gavin and gang.”
★★★★★
New kitchen & wall removal
“We are extremely pleased with the work that has been completed. … Everything was kept safely and out of the way at the end of the day. They all worked very efficiently to a very high standard.”
★★★★★
Builder · Google
“A true craftsman, a master of his trade. A man of integrity and reliability always prompt and courteous. … I’d highly recommend this exceptional builder and his skilled team.”
★★★★★
Extension · Google
“Gwynedd Construction provides excellent, quality professional service, project managed my extension, very impressive, on time and within budget, as well as offering innovative design advice along the way, highly recommended.”
★★★★★
New patio · Facebook
“Hogia clên ac taclus iawn ei gwaith. Glanhau bob nos cyn gadael ac yn hollol ddi-drafferth. Awgrymu’r cwmni’n gryf!”“Friendly lads, very tidy work. They cleaned up every night before they left, and it was completely hassle-free. Highly recommend the company!”
★★★★★
Building work · Google
“It was a pleasure to welcome this friendly professional and trustworthy crew every morning. Never let me down, in fact went out of their way to find solutions to unforeseen issues.”
★★★★★
New kitchen · Google
“Once the decision to FINALLY get a new kitchen was made the nerves set in. There was no need, Gavin and his team made everything right. Communication was excellent … And best of all done within timescale agreed. Very Happy.”
★★★★★
Office repairs · Google
“I’ve used Gwynedd Construction on several occasions for general repairs in my office, and every time the service has been exceptional. Gavin, the owner, is professional, reliable, and clearly takes pride in the work his team delivers. … Highly recommended if you’re looking for quality workmanship in North Wales.”
★★★★★
Garage conversion
“Can't speak highly enough of Gwynedd Construction Ltd. They completed the work on time and to an extremely high standard. Nothing was too much trouble … Will definitely use them again.”
★★★★★
Building project · Google
“I must commend the excellent high-quality construction work that was delivered. … The planning phase was executed to perfection … the team's ability to effectively manage unexpected changes truly stood out. … 100% recommend.”
★★★★★
Bedroom work · Google
“Gwynedd Construction did an excellent job on the work i had done on my bedroom. They were very professional and polite. They cleaned up afterwards and you wouldn't have known they had done work on my bedroom.”
★★★★★
Walls removed, 3 RSJs fitted
“Gavin and Geraint were extremely professional from our very first meeting. They are two hard working, trustworthy, reliable and extremely tidy workmen. … Can't recommend them highly enough.”
★★★★★
Renovation project · Google
“Can't speak highly enough of Gwynedd Construction and the incredible work they did on our one-year renovation project. … What impressed us most was their ability to handle unexpected challenges with ease, offering creative solutions while staying on schedule and within budget.”
★★★★★
Extension, garage & patio · Google
“The team built a large extension at the back of my property and a detached garage … I then had the team back to do a patio and a retaining wall. Also very clean and tidy workers … Good job Gavin and gang.”
★★★★★
New kitchen & wall removal
“We are extremely pleased with the work that has been completed. … Everything was kept safely and out of the way at the end of the day. They all worked very efficiently to a very high standard.”
★★★★★
Builder · Google
“A true craftsman, a master of his trade. A man of integrity and reliability always prompt and courteous. … I’d highly recommend this exceptional builder and his skilled team.”
★★★★★
Extension · Google
“Gwynedd Construction provides excellent, quality professional service, project managed my extension, very impressive, on time and within budget, as well as offering innovative design advice along the way, highly recommended.”
★★★★★
New patio · Facebook
“Hogia clên ac taclus iawn ei gwaith. Glanhau bob nos cyn gadael ac yn hollol ddi-drafferth. Awgrymu’r cwmni’n gryf!”“Friendly lads, very tidy work. They cleaned up every night before they left, and it was completely hassle-free. Highly recommend the company!”
★★★★★
Building work · Google
“It was a pleasure to welcome this friendly professional and trustworthy crew every morning. Never let me down, in fact went out of their way to find solutions to unforeseen issues.”
Why us
Why people pick Gwynedd Construction
A local builder you can reach on the phone, who turns up when they say and leaves the job tidy.
5.0★★★★★on Google
01
Local to Gwynedd
Based in Pontrug, just outside Caernarfon, with more than 15 years in construction.
02
An established company
Gwynedd Construction has been a limited company since 2016.
03
5.0 stars on Google
And 100% of people who reviewed us on Facebook recommend us.
04
One team, start to finish
From the groundwork to the plastering, so you're not passed between firms.
05
On time and tidy
The site is kept clean as we go, and you're kept up to date the whole way.
Based in PontrugJust outside Caernarfon, Gwynedd
Areas covered
Other places we work
As well as Llanberis and Llanrug, we work across Gwynedd and Anglesey. Not on the list? Give us a ring and ask.
