PROPERTY ENERGY EFFICIENCY CERTIFICATE DETAILS
William Street, BANGOR, LL57 1BG
Introduction
Energy Performance Certificates (EPCs) are designed to tell you how efficient a building is and provides a rating between A (very efficient) and G which is inefficient. It helps to identify how costly it will be to light and heat a property and what the carbon dioxide emissions are likely to be.
An EPC needs to be provided as part of the process of selling or renting a house and should be availale as soon as the property is marketed. An EPC may only be produced by an approved domestic energy assessor and each certificate is valid for 10 years.
Additionally, an EPC will highlight potential efficiency improvements that could be made to the property, an estimated cost for implementation and the likely savings that can be made as a result. These costs and savings are for a typical household in that property and not specific to you or your family.
Certificates issued for William Street, LL57 1BG are shown below and the data are updated monthly for England and Wales and quarterly for properties in Scotland.
Data are provided by the Department for Levelling Up, Housing and Communities.
Energy Performance Certificates Generated for William Street, BANGOR, LL57 1BG
Period Covered:
2008 - 31 January 2025
Address
Inspection Date
Current
Potential
Property Type
Built Form
Constructed
Address
1 Plas Yr Wylan, William Street
Date
10 Jan 2017
Current
Potential
84
84
Property Type
Flat
Built Form
Detached
Constructed
N/A
Certificate History
10 Jan 2017
84
84
Total Floor Area
62 sq m
Current CO2 Emissions Level
0.9
Potential CO2 Emissions Level
0.9
CO2 per sq m per Year
15
Mains Gas Available
No
Habitable Rooms
0
Number of Extensions
0
Address
11 William Street
Date
10 Jul 2013
Current
Potential
78
88
Property Type
House
Built Form
Mid-Terrace
Constructed
1900-1929
Certificate History
10 Jul 2013
78
88
2 Jul 2009
62
67
Total Floor Area
76 sq m
Current CO2 Emissions Level
2.0
Potential CO2 Emissions Level
0.8
CO2 per sq m per Year
26
Mains Gas Available
Yes
Habitable Rooms
4
Number of Extensions
1
Address
13 William Street
Date
12 Dec 2024
Current
Potential
73
88
Property Type
House
Built Form
Mid-Terrace
Constructed
1900-1929
Certificate History
12 Dec 2024
73
88
15 Jan 2014
60
86
Total Floor Area
74 sq m
Current CO2 Emissions Level
2.4
Potential CO2 Emissions Level
0.9
CO2 per sq m per Year
32
Mains Gas Available
Yes
Habitable Rooms
4
Number of Extensions
1
Address
14 William Street
Date
22 Dec 2025
Current
Potential
71
77
Property Type
N/A
Built Form
N/A
Constructed
N/A
Certificate History
22 Dec 2025
71
77
17 Jul 2014
69
69
Total Floor Area
43 sq m
Current CO2 Emissions Level
1.4
Potential CO2 Emissions Level
1.0
CO2 per sq m per Year
32
Mains Gas Available
Yes
Habitable Rooms
3
Number of Extensions
0
Address
15 William Street
Date
7 Dec 2015
Current
Potential
63
80
Property Type
House
Built Form
Mid-Terrace
Constructed
1900-1929
Certificate History
7 Dec 2015
63
80
Total Floor Area
82 sq m
Current CO2 Emissions Level
3.7
Potential CO2 Emissions Level
2.0
CO2 per sq m per Year
46
Mains Gas Available
Yes
Habitable Rooms
5
Number of Extensions
1
Address
16 William Street
Date
16 Jul 2014
Current
Potential
67
68
Property Type
Flat
Built Form
Detached
Constructed
1950-1966
Certificate History
16 Jul 2014
67
68
23 Apr 2013
77
77
Total Floor Area
52 sq m
Current CO2 Emissions Level
2.0
Potential CO2 Emissions Level
1.9
CO2 per sq m per Year
39
Mains Gas Available
Yes
Habitable Rooms
3
Number of Extensions
0
Address
19 William Street
Date
3 Jan 2011
Current
Potential
51
58
Property Type
House
Built Form
Mid-Terrace
Constructed
1900-1929
Certificate History
3 Jan 2011
51
58
Total Floor Area
76 sq m
Current CO2 Emissions Level
5.3
Potential CO2 Emissions Level
4.3
CO2 per sq m per Year
59
Mains Gas Available
Yes
Habitable Rooms
5
Number of Extensions
1
Address
19 WILLIAM STREET, BANGOR
Date
22 Dec 2020
Current
Potential
65
84
Property Type
House
Built Form
Mid-Terrace
Constructed
before 1900
Certificate History
22 Dec 2020
65
84
Total Floor Area
81 sq m
Current CO2 Emissions Level
3.5
Potential CO2 Emissions Level
1.5
CO2 per sq m per Year
43
Mains Gas Available
Yes
Habitable Rooms
5
Number of Extensions
1
Address
2 William Street
Date
11 Jun 2024
Current
Potential
76
78
Property Type
Flat
Built Form
Detached
Constructed
1950-1966
Certificate History
11 Jun 2024
76
78
27 Feb 2013
76
79
Total Floor Area
50 sq m
Current CO2 Emissions Level
1.5
Potential CO2 Emissions Level
1.3
CO2 per sq m per Year
29
Mains Gas Available
Yes
Habitable Rooms
3
Number of Extensions
0
Address
21 William Street
Date
7 Apr 2018
Current
Potential
63
80
Property Type
House
Built Form
Mid-Terrace
Constructed
before 1900
Certificate History
7 Apr 2018
63
80
4 Feb 2011
66
67
Total Floor Area
88 sq m
Current CO2 Emissions Level
4.0
Potential CO2 Emissions Level
2.1
CO2 per sq m per Year
46
Mains Gas Available
Yes
Habitable Rooms
5
Number of Extensions
1
Address
25 William Street
Date
1 Mar 2022
Current
Potential
70
87
Property Type
House
Built Form
Mid-Terrace
Constructed
1900-1929
Certificate History
1 Mar 2022
70
87
31 Dec 2010
50
67
Total Floor Area
74 sq m
Current CO2 Emissions Level
2.7
Potential CO2 Emissions Level
1.0
CO2 per sq m per Year
36
Mains Gas Available
Yes
Habitable Rooms
5
Number of Extensions
1
Address
27 William Street
Date
11 Jul 2013
Current
Potential
63
81
Property Type
House
Built Form
Mid-Terrace
Constructed
1900-1929
Certificate History
11 Jul 2013
63
81
Total Floor Area
73 sq m
Current CO2 Emissions Level
3.2
Potential CO2 Emissions Level
1.6
CO2 per sq m per Year
44
Mains Gas Available
Yes
Habitable Rooms
4
Number of Extensions
1
Address
29 William Street
Date
15 Feb 2019
Current
Potential
72
86
Property Type
House
Built Form
Mid-Terrace
Constructed
1900-1929
Certificate History
15 Feb 2019
72
86
Total Floor Area
68 sq m
Current CO2 Emissions Level
2.3
Potential CO2 Emissions Level
1.1
CO2 per sq m per Year
33
Mains Gas Available
Yes
Habitable Rooms
4
Number of Extensions
1
Address
3 William Street
Date
13 Sep 2016
Current
Potential
63
84
Property Type
House
Built Form
Mid-Terrace
Constructed
1900-1929
Certificate History
13 Sep 2016
63
84
Total Floor Area
70 sq m
Current CO2 Emissions Level
3.3
Potential CO2 Emissions Level
1.3
CO2 per sq m per Year
47
Mains Gas Available
Yes
Habitable Rooms
4
Number of Extensions
1
Address
31 William Street
Date
7 Feb 2024
Current
Potential
71
85
Property Type
House
Built Form
Mid-Terrace
Constructed
before 1900
Certificate History
7 Feb 2024
71
85
12 Feb 2014
72
88
Total Floor Area
84 sq m
Current CO2 Emissions Level
2.8
Potential CO2 Emissions Level
1.4
CO2 per sq m per Year
33
Mains Gas Available
Yes
Habitable Rooms
5
Number of Extensions
2
Address
33 William Street
Date
25 Apr 2023
Current
Potential
64
85
Property Type
House
Built Form
End-Terrace
Constructed
before 1900
Certificate History
25 Apr 2023
64
85
9 May 2019
58
83
Total Floor Area
135 sq m
Current CO2 Emissions Level
5.5
Potential CO2 Emissions Level
2.1
CO2 per sq m per Year
41
Mains Gas Available
Yes
Habitable Rooms
6
Number of Extensions
0
Address
4 William Street
Date
11 Jun 2024
Current
Potential
78
78
Property Type
Flat
Built Form
Detached
Constructed
1950-1966
Certificate History
11 Jun 2024
78
78
17 Jul 2014
68
69
Total Floor Area
50 sq m
Current CO2 Emissions Level
1.2
Potential CO2 Emissions Level
1.2
CO2 per sq m per Year
24
Mains Gas Available
Yes
Habitable Rooms
3
Number of Extensions
0
Address
5 WILLIAM STREET
Date
21 Sep 2020
Current
Potential
70
88
Property Type
House
Built Form
Mid-Terrace
Constructed
1900-1929
Certificate History
21 Sep 2020
70
88
Total Floor Area
76 sq m
Current CO2 Emissions Level
2.7
Potential CO2 Emissions Level
0.9
CO2 per sq m per Year
36
Mains Gas Available
Yes
Habitable Rooms
5
Number of Extensions
2
Address
5 William Street
Date
16 Apr 2010
Current
Potential
60
70
Property Type
House
Built Form
Mid-Terrace
Constructed
before 1900
Certificate History
16 Apr 2010
60
70
Total Floor Area
78 sq m
Current CO2 Emissions Level
4.4
Potential CO2 Emissions Level
3.2
CO2 per sq m per Year
56
Mains Gas Available
Yes
Habitable Rooms
6
Number of Extensions
2
Address
6 William Street
Date
16 Jul 2014
Current
Potential
66
66
Property Type
Flat
Built Form
Detached
Constructed
1950-1966
Certificate History
16 Jul 2014
66
66
Total Floor Area
52 sq m
Current CO2 Emissions Level
2.2
Potential CO2 Emissions Level
2.2
CO2 per sq m per Year
43
Mains Gas Available
Yes
Habitable Rooms
3
Number of Extensions
0
Address
7 William Street
Date
25 Jan 2016
Current
Potential
67
85
Property Type
House
Built Form
Mid-Terrace
Constructed
1900-1929
Certificate History
25 Jan 2016
67
85
Total Floor Area
85 sq m
Current CO2 Emissions Level
3.3
Potential CO2 Emissions Level
1.4
CO2 per sq m per Year
39
Mains Gas Available
Yes
Habitable Rooms
4
Number of Extensions
2
Address
9 William Street
Date
9 May 2022
Current
Potential
73
86
Property Type
House
Built Form
Mid-Terrace
Constructed
1900-1929
Certificate History
9 May 2022
73
86
18 Apr 2012
51
81
Total Floor Area
76 sq m
Current CO2 Emissions Level
2.5
Potential CO2 Emissions Level
1.2
CO2 per sq m per Year
32
Mains Gas Available
Yes
Habitable Rooms
5
Number of Extensions
1
Bands
Energy Performance Certificate Notes
There are a number of reasons that certificates are excluded from the dataset;
- The holder of the energy certificate has 'opted-out' of disclosure
- The certificate is excluded on the grounds of national security
- Certificates that are marked as 'cancelled' or 'not for issue'
Certificates are grouped together by the property reference identifier rather than the postal address with a view to showing the history of changes made to properties over time. Sometimes, one property may exist as multiple entries in the table instead and this is as a result of inconsistent building references being used on each prepared certificate.
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Contains Royal Mail data © Royal Mail copyright and Database right 2026.