PROPERTY ENERGY EFFICIENCY CERTIFICATE DETAILS
Onslow Square, LONDON, SW7 3NJ
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 Onslow Square, SW7 3NJ 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 Onslow Square, LONDON, SW7 3NJ
Period Covered:
2008 - 31 January 2025
Address
Inspection Date
Current
Potential
Property Type
Built Form
Constructed
Address
1 Onslow Square
Date
25 Nov 2010
Current
Potential
61
64
Property Type
Flat
Built Form
End-Terrace
Constructed
before 1900
Certificate History
25 Nov 2010
61
64
5 Apr 2010
57
60
Total Floor Area
110 sq m
Current CO2 Emissions Level
5.2
Potential CO2 Emissions Level
5.1
CO2 per sq m per Year
48
Mains Gas Available
Yes
Habitable Rooms
4
Number of Extensions
0
Address
13 Onslow Square
Date
29 Oct 2019
Current
Potential
68
81
Property Type
Flat
Built Form
End-Terrace
Constructed
before 1900
Certificate History
29 Oct 2019
68
81
Total Floor Area
100 sq m
Current CO2 Emissions Level
3.4
Potential CO2 Emissions Level
1.8
CO2 per sq m per Year
34
Mains Gas Available
Yes
Habitable Rooms
3
Number of Extensions
0
Address
21 Onslow Square
Date
17 Apr 2025
Current
Potential
71
81
Property Type
Flat
Built Form
Mid-Terrace
Constructed
before 1900
Certificate History
17 Apr 2025
71
81
16 Jan 2015
50
73
Total Floor Area
116 sq m
Current CO2 Emissions Level
3.4
Potential CO2 Emissions Level
2.0
CO2 per sq m per Year
29
Mains Gas Available
Yes
Habitable Rooms
4
Number of Extensions
1
Address
9 ONSLOW SQUARE
Date
10 Jun 2021
Current
Potential
77
83
Property Type
Flat
Built Form
Enclosed Mid-Terrace
Constructed
before 1900
Certificate History
10 Jun 2021
77
83
Total Floor Area
34 sq m
Current CO2 Emissions Level
1.9
Potential CO2 Emissions Level
1.4
CO2 per sq m per Year
55
Mains Gas Available
No
Habitable Rooms
1
Number of Extensions
0
Address
9 Onslow Square
Date
4 Apr 2011
Current
Potential
55
63
Property Type
Flat
Built Form
Mid-Terrace
Constructed
before 1900
Certificate History
4 Apr 2011
55
63
25 Mar 2011
69
70
Total Floor Area
31 sq m
Current CO2 Emissions Level
3.2
Potential CO2 Emissions Level
2.8
CO2 per sq m per Year
102
Mains Gas Available
No
Habitable Rooms
1
Number of Extensions
0
Address
9a Onslow Square
Date
10 Jul 2018
Current
Potential
66
78
Property Type
Flat
Built Form
End-Terrace
Constructed
before 1900
Certificate History
10 Jul 2018
66
78
Total Floor Area
72 sq m
Current CO2 Emissions Level
2.8
Potential CO2 Emissions Level
1.6
CO2 per sq m per Year
39
Mains Gas Available
Yes
Habitable Rooms
3
Number of Extensions
0
Address
Flat 1, 1 Onslow Square
Date
2 Sep 2019
Current
Potential
60
78
Property Type
Flat
Built Form
End-Terrace
Constructed
before 1900
Certificate History
2 Sep 2019
60
78
Total Floor Area
111 sq m
Current CO2 Emissions Level
4.8
Potential CO2 Emissions Level
2.3
CO2 per sq m per Year
43
Mains Gas Available
Yes
Habitable Rooms
3
Number of Extensions
0
Address
Flat 1, 11, Onslow Square
Date
28 Oct 2019
Current
Potential
58
78
Property Type
Flat
Built Form
Detached
Constructed
before 1900
Certificate History
28 Oct 2019
58
78
24 Sep 2009
67
69
10 Dec 2008
67
74
Total Floor Area
100 sq m
Current CO2 Emissions Level
4.7
Potential CO2 Emissions Level
2.1
CO2 per sq m per Year
47
Mains Gas Available
Yes
Habitable Rooms
3
Number of Extensions
1
Address
Flat 1, 17 Onslow Square
Date
10 Oct 2016
Current
Potential
69
81
Property Type
Flat
Built Form
Mid-Terrace
Constructed
before 1900
Certificate History
10 Oct 2016
69
81
Total Floor Area
116 sq m
Current CO2 Emissions Level
3.8
Potential CO2 Emissions Level
2.0
CO2 per sq m per Year
32
Mains Gas Available
Yes
Habitable Rooms
4
Number of Extensions
0
Address
Flat 1/A, 25, Onslow Square
Date
21 Jan 2014
Current
Potential
70
78
Property Type
Flat
Built Form
Mid-Terrace
Constructed
before 1900
Certificate History
21 Jan 2014
70
78
27 Aug 2009
65
65
Total Floor Area
33 sq m
Current CO2 Emissions Level
1.6
Potential CO2 Emissions Level
1.0
CO2 per sq m per Year
47
Mains Gas Available
Yes
Habitable Rooms
3
Number of Extensions
0
Address
Flat 10, 25, Onslow Square
Date
5 May 2011
Current
Potential
84
86
Property Type
Flat
Built Form
Mid-Terrace
Constructed
1996-2002
Certificate History
5 May 2011
84
86
14 Apr 2010
67
70
Total Floor Area
134 sq m
Current CO2 Emissions Level
1.9
Potential CO2 Emissions Level
1.7
CO2 per sq m per Year
14
Mains Gas Available
No
Habitable Rooms
4
Number of Extensions
0
Address
Flat 11, 25 Onslow Square
Date
23 Mar 2022
Current
Potential
48
77
Property Type
Flat
Built Form
Mid-Terrace
Constructed
1950-1966
Certificate History
23 Mar 2022
48
77
10 Jun 2009
45
46
Total Floor Area
94 sq m
Current CO2 Emissions Level
6.1
Potential CO2 Emissions Level
2.2
CO2 per sq m per Year
64
Mains Gas Available
Yes
Habitable Rooms
3
Number of Extensions
0
Address
Flat 12, 25 Onslow Square
Date
12 Feb 2024
Current
Potential
48
67
Property Type
Flat
Built Form
End-Terrace
Constructed
1900-1929
Certificate History
12 Feb 2024
48
67
Total Floor Area
116 sq m
Current CO2 Emissions Level
7.1
Potential CO2 Emissions Level
4.2
CO2 per sq m per Year
61
Mains Gas Available
No
Habitable Rooms
4
Number of Extensions
0
Address
Flat 1a, 25 Onslow Square
Date
24 Jan 2024
Current
Potential
74
78
Property Type
Flat
Built Form
Enclosed Mid-Terrace
Constructed
before 1900
Certificate History
24 Jan 2024
74
78
Total Floor Area
40 sq m
Current CO2 Emissions Level
1.4
Potential CO2 Emissions Level
1.1
CO2 per sq m per Year
35
Mains Gas Available
Yes
Habitable Rooms
2
Number of Extensions
0
Address
Flat 2, 11 Onslow Square
Date
14 Jan 2025
Current
Potential
73
82
Property Type
Flat
Built Form
Mid-Terrace
Constructed
before 1900
Certificate History
14 Jan 2025
73
82
3 Dec 2014
70
82
Total Floor Area
108 sq m
Current CO2 Emissions Level
3.0
Potential CO2 Emissions Level
1.8
CO2 per sq m per Year
28
Mains Gas Available
Yes
Habitable Rooms
4
Number of Extensions
0
Address
Flat 2, 17 Onslow Square
Date
2 Mar 2023
Current
Potential
72
83
Property Type
Flat
Built Form
Mid-Terrace
Constructed
1900-1929
Certificate History
2 Mar 2023
72
83
20 Feb 2012
64
70
Total Floor Area
113 sq m
Current CO2 Emissions Level
3.2
Potential CO2 Emissions Level
1.7
CO2 per sq m per Year
28
Mains Gas Available
Yes
Habitable Rooms
3
Number of Extensions
0
Address
Flat 2, 23 Onslow Square
Date
8 Dec 2016
Current
Potential
72
84
Property Type
Flat
Built Form
Mid-Terrace
Constructed
before 1900
Certificate History
8 Dec 2016
72
84
Total Floor Area
117 sq m
Current CO2 Emissions Level
3.2
Potential CO2 Emissions Level
1.5
CO2 per sq m per Year
27
Mains Gas Available
Yes
Habitable Rooms
4
Number of Extensions
0
Address
Flat 2, 5 Onslow Square
Date
15 Nov 2012
Current
Potential
54
78
Property Type
Flat
Built Form
End-Terrace
Constructed
before 1900
Certificate History
15 Nov 2012
54
78
Total Floor Area
113 sq m
Current CO2 Emissions Level
6.0
Potential CO2 Emissions Level
2.6
CO2 per sq m per Year
54
Mains Gas Available
Yes
Habitable Rooms
3
Number of Extensions
0
Address
Flat 3, 11 Onslow Square
Date
10 Jan 2024
Current
Potential
71
80
Property Type
Flat
Built Form
End-Terrace
Constructed
before 1900
Certificate History
10 Jan 2024
71
80
20 Oct 2010
65
67
Total Floor Area
82 sq m
Current CO2 Emissions Level
2.8
Potential CO2 Emissions Level
1.7
CO2 per sq m per Year
33
Mains Gas Available
Yes
Habitable Rooms
3
Number of Extensions
0
Address
Flat 3, 23 Onslow Square
Date
13 Sep 2024
Current
Potential
75
82
Property Type
Flat
Built Form
Mid-Terrace
Constructed
1900-1929
Certificate History
13 Sep 2024
75
82
15 Sep 2014
76
86
25 Oct 2011
70
75
17 Oct 2008
75
81
Total Floor Area
64 sq m
Current CO2 Emissions Level
1.7
Potential CO2 Emissions Level
1.1
CO2 per sq m per Year
27
Mains Gas Available
Yes
Habitable Rooms
4
Number of Extensions
0
Address
Flat 3, 5 Onslow Square
Date
7 Jan 2022
Current
Potential
60
76
Property Type
Flat
Built Form
Semi-Detached
Constructed
1900-1929
Certificate History
7 Jan 2022
60
76
23 Jun 2009
50
52
Total Floor Area
117 sq m
Current CO2 Emissions Level
5.4
Potential CO2 Emissions Level
2.9
CO2 per sq m per Year
46
Mains Gas Available
Yes
Habitable Rooms
5
Number of Extensions
0
Address
Flat 4, 11 Onslow Square
Date
8 Feb 2023
Current
Potential
76
84
Property Type
Flat
Built Form
Mid-Terrace
Constructed
1900-1929
Certificate History
8 Feb 2023
76
84
22 Oct 2012
74
84
Total Floor Area
111 sq m
Current CO2 Emissions Level
2.7
Potential CO2 Emissions Level
1.6
CO2 per sq m per Year
24
Mains Gas Available
Yes
Habitable Rooms
5
Number of Extensions
0
Address
Flat 4, 17 Onslow Square
Date
16 Sep 2025
Current
Potential
80
85
Property Type
Flat
Built Form
Not Recorded
Constructed
1900-1929
Certificate History
16 Sep 2025
80
85
26 Sep 2014
70
85
16 Oct 2008
70
77
Total Floor Area
110 sq m
Current CO2 Emissions Level
1.9
Potential CO2 Emissions Level
1.2
CO2 per sq m per Year
17
Mains Gas Available
Yes
Habitable Rooms
4
Number of Extensions
0
Address
Flat 4, 25, Onslow Square
Date
23 Sep 2010
Current
Potential
63
65
Property Type
Flat
Built Form
Detached
Constructed
1900-1929
Certificate History
23 Sep 2010
63
65
Total Floor Area
173 sq m
Current CO2 Emissions Level
7.0
Potential CO2 Emissions Level
6.9
CO2 per sq m per Year
41
Mains Gas Available
Yes
Habitable Rooms
6
Number of Extensions
0
Address
Flat 4, 5, Onslow Square
Date
15 Aug 2012
Current
Potential
59
75
Property Type
Flat
Built Form
Mid-Terrace
Constructed
before 1900
Certificate History
15 Aug 2012
59
75
7 Aug 2012
55
75
17 Dec 2010
61
62
Total Floor Area
101 sq m
Current CO2 Emissions Level
5.3
Potential CO2 Emissions Level
2.5
CO2 per sq m per Year
53
Mains Gas Available
Yes
Habitable Rooms
4
Number of Extensions
0
Address
FLAT 5, 11 ONSLOW SQUARE
Date
30 Sep 2020
Current
Potential
70
82
Property Type
Flat
Built Form
Mid-Terrace
Constructed
1900-1929
Certificate History
30 Sep 2020
70
82
Total Floor Area
110 sq m
Current CO2 Emissions Level
3.4
Potential CO2 Emissions Level
1.7
CO2 per sq m per Year
31
Mains Gas Available
Yes
Habitable Rooms
3
Number of Extensions
0
Address
Flat 5, 25, Onslow Square
Date
27 Aug 2015
Current
Potential
70
80
Property Type
Flat
Built Form
Mid-Terrace
Constructed
before 1900
Certificate History
27 Aug 2015
70
80
Total Floor Area
60 sq m
Current CO2 Emissions Level
2.2
Potential CO2 Emissions Level
1.4
CO2 per sq m per Year
37
Mains Gas Available
No
Habitable Rooms
2
Number of Extensions
0
Address
Flat 5, 5 Onslow Square
Date
25 Apr 2022
Current
Potential
72
82
Property Type
Flat
Built Form
Semi-Detached
Constructed
1900-1929
Certificate History
25 Apr 2022
72
82
24 Nov 2009
72
74
Total Floor Area
123 sq m
Current CO2 Emissions Level
3.6
Potential CO2 Emissions Level
2.1
CO2 per sq m per Year
29
Mains Gas Available
No
Habitable Rooms
4
Number of Extensions
0
Address
Flat 6, 11 Onslow Square
Date
4 Mar 2022
Current
Potential
75
82
Property Type
Flat
Built Form
Mid-Terrace
Constructed
1900-1929
Certificate History
4 Mar 2022
75
82
12 Jan 2012
75
76
17 Nov 2011
73
74
Total Floor Area
105 sq m
Current CO2 Emissions Level
2.6
Potential CO2 Emissions Level
1.6
CO2 per sq m per Year
25
Mains Gas Available
Yes
Habitable Rooms
4
Number of Extensions
0
Address
Flat 6, 25, Onslow Square
Date
27 Aug 2015
Current
Potential
70
80
Property Type
Flat
Built Form
Mid-Terrace
Constructed
before 1900
Certificate History
27 Aug 2015
70
80
Total Floor Area
60 sq m
Current CO2 Emissions Level
2.2
Potential CO2 Emissions Level
1.4
CO2 per sq m per Year
37
Mains Gas Available
No
Habitable Rooms
2
Number of Extensions
0
Address
Flat 6, 5 Onslow Square
Date
8 Dec 2021
Current
Potential
56
78
Property Type
Flat
Built Form
Enclosed End-Terrace
Constructed
1930-1949
Certificate History
8 Dec 2021
56
78
15 Aug 2016
49
78
6 Jan 2010
52
63
19 Feb 2009
47
59
Total Floor Area
106 sq m
Current CO2 Emissions Level
5.2
Potential CO2 Emissions Level
2.2
CO2 per sq m per Year
49
Mains Gas Available
Yes
Habitable Rooms
3
Number of Extensions
0
Address
Flat 7, 11 Onslow Square
Date
8 Nov 2019
Current
Potential
67
81
Property Type
Flat
Built Form
End-Terrace
Constructed
1900-1929
Certificate History
8 Nov 2019
67
81
29 Mar 2009
78
80
Total Floor Area
83 sq m
Current CO2 Emissions Level
2.9
Potential CO2 Emissions Level
1.4
CO2 per sq m per Year
35
Mains Gas Available
Yes
Habitable Rooms
4
Number of Extensions
0
Address
Flat 7, 5 Onslow Square
Date
8 Nov 2024
Current
Potential
58
74
Property Type
Flat
Built Form
Mid-Terrace
Constructed
1900-1929
Certificate History
8 Nov 2024
58
74
Total Floor Area
121 sq m
Current CO2 Emissions Level
5.8
Potential CO2 Emissions Level
3.3
CO2 per sq m per Year
47
Mains Gas Available
No
Habitable Rooms
6
Number of Extensions
1
Address
Flat 8, 11, Onslow Square
Date
13 Sep 2018
Current
Potential
56
66
Property Type
Flat
Built Form
Mid-Terrace
Constructed
1900-1929
Certificate History
13 Sep 2018
56
66
24 Oct 2010
32
42
17 Oct 2010
41
56
Total Floor Area
70 sq m
Current CO2 Emissions Level
3.9
Potential CO2 Emissions Level
2.8
CO2 per sq m per Year
55
Mains Gas Available
Yes
Habitable Rooms
3
Number of Extensions
0
Address
Flat 8, 25 Onslow Square
Date
7 Oct 2024
Current
Potential
75
81
Property Type
Flat
Built Form
Mid-Terrace
Constructed
before 1900
Certificate History
7 Oct 2024
75
81
23 Jul 2012
63
81
Total Floor Area
136 sq m
Current CO2 Emissions Level
3.4
Potential CO2 Emissions Level
2.4
CO2 per sq m per Year
25
Mains Gas Available
Yes
Habitable Rooms
3
Number of Extensions
1
Address
Flat 8, 5 Onslow Square
Date
16 Feb 2024
Current
Potential
45
79
Property Type
Flat
Built Form
Semi-Detached
Constructed
1900-1929
Certificate History
16 Feb 2024
45
79
Total Floor Area
211 sq m
Current CO2 Emissions Level
12.0
Potential CO2 Emissions Level
3.5
CO2 per sq m per Year
55
Mains Gas Available
No
Habitable Rooms
5
Number of Extensions
0
Address
FLAT 9, 11 ONSLOW SQUARE
Date
29 Apr 2021
Current
Potential
64
66
Property Type
Flat
Built Form
Mid-Terrace
Constructed
1900-1929
Certificate History
29 Apr 2021
64
66
Total Floor Area
74 sq m
Current CO2 Emissions Level
3.1
Potential CO2 Emissions Level
2.9
CO2 per sq m per Year
42
Mains Gas Available
Yes
Habitable Rooms
3
Number of Extensions
0
Address
Flat 9, 11, Onslow Square
Date
8 May 2011
Current
Potential
49
66
Property Type
Flat
Built Form
End-Terrace
Constructed
before 1900
Certificate History
8 May 2011
49
66
Total Floor Area
68 sq m
Current CO2 Emissions Level
4.8
Potential CO2 Emissions Level
2.9
CO2 per sq m per Year
70
Mains Gas Available
Yes
Habitable Rooms
2
Number of Extensions
0
Address
Ground Floor Flat, 19 Onslow Square
Date
1 Feb 2010
Current
Potential
37
45
Property Type
Maisonette
Built Form
Mid-Terrace
Constructed
before 1900
Certificate History
1 Feb 2010
37
45
Total Floor Area
145 sq m
Current CO2 Emissions Level
11.1
Potential CO2 Emissions Level
9.4
CO2 per sq m per Year
76
Mains Gas Available
Yes
Habitable Rooms
4
Number of Extensions
1
Address
Ground Floor Flat, Park Cottage
Date
3 Apr 2013
Current
Potential
35
79
Property Type
Flat
Built Form
Detached
Constructed
before 1900
Certificate History
3 Apr 2013
35
79
Total Floor Area
41 sq m
Current CO2 Emissions Level
3.7
Potential CO2 Emissions Level
2.1
CO2 per sq m per Year
92
Mains Gas Available
No
Habitable Rooms
2
Number of Extensions
0
Address
Park House, 7-11 Onslow Square
Date
3 Apr 2013
Current
Potential
36
59
Property Type
House
Built Form
Detached
Constructed
before 1900
Certificate History
3 Apr 2013
36
59
Total Floor Area
996 sq m
Current CO2 Emissions Level
66.0
Potential CO2 Emissions Level
43.0
CO2 per sq m per Year
67
Mains Gas Available
Yes
Habitable Rooms
14
Number of Extensions
3
Address
Top Flat, Park Cottage
Date
3 Apr 2013
Current
Potential
22
56
Property Type
Flat
Built Form
Detached
Constructed
before 1900
Certificate History
3 Apr 2013
22
56
Total Floor Area
49 sq m
Current CO2 Emissions Level
9.5
Potential CO2 Emissions Level
5.2
CO2 per sq m per Year
195
Mains Gas Available
No
Habitable Rooms
2
Number of Extensions
0
Address
Upper Ground Floor Flat, 13 Onslow Square
Date
10 Dec 2008
Current
Potential
64
71
Property Type
Flat
Built Form
Mid-Terrace
Constructed
1900-1929
Certificate History
10 Dec 2008
64
71
Total Floor Area
101 sq m
Current CO2 Emissions Level
4.0
Potential CO2 Emissions Level
3.3
CO2 per sq m per Year
39
Mains Gas Available
Yes
Habitable Rooms
3
Number of Extensions
0
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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