Scottish house condition survey: 2017 key findings

2 Key Attributes of the Scottish Housing Stock

11. The Scottish House Condition Survey provides a snapshot of the Scottish housing stock in each survey year. This chapter sets out information on the basic attributes of occupied Scottish dwellings as captured in 2017. Subsequent chapters build on this and provide more details on energy efficiency, fuel poverty, housing quality and disrepair.

12. The following topics are included:

• the construction age and general types of Scottish domestic buildings;
• the dwellings’ location in relation to the gas network and the type of fuel used to heat them;
• the relationship between the dwellings’ attributes and household tenure; and
• the makeup of the households who live in them.

2.1 Dwelling Age and Type

13. The age of construction and the built form of a dwelling has consequences for energy performance, the improvement potential, affordability and living conditions. For example, dwellings built since 1982 comply with standards for minimum levels of energy efficiency and airtightness.

14. More information on the main dwelling types used in the SHCS is provided in section 7.9.1.

15. At the same time, types of dwellings can differ in terms of the size of exposed areas: fewer exposed areas of wall, or shielding by dwellings above and below, lead to lower levels of heat loss than in buildings with fewer sheltered sides.

16. The Scottish housing stock is diverse and varies across the country and between rural and urban areas. However, some common types can be recognised in Figure 1:

• Old (pre-1919) detached houses (around 94,000) and tenement flats (182,000)
• More modern post-1982 detached houses (256,000) and tenements (189,000)
• Post-war terraced houses (349,000 built between 1945 and 1982)
• Semi-detached houses, common across all age bands and accounting for around 20% of the stock alone.

17. These six broad categories account for 63% of the overall housing stock. However, there is also a good deal of variability within these groups; even among pre-1919 tenement flats of the type common in Edinburgh and Glasgow, there is a wide range of sizes, shapes and areas of exposure (for example in top floor flats the roof is exposed) which affects their energy efficiency and the living conditions they provide.

Figure 1: Number of Occupied Scottish Dwellings by Age Band and Type, 2017

18. The proportion of the stock in each dwelling age band and type is provided in Table 1. Numbers of dwellings of each age group and type are shown in Table 2.

Table 1: Proportion of Occupied Dwellings by Age Band and Type, 2017 (Percentage of Whole Stock)

Age of dwelling	Type of Dwelling
	Detached	Semi-detached	Terraced	Tenement	Other flats	Total
pre-1919	4%	3%	3%	7%	2%	19%
1919-1944	2%	3%	1%	2%	4%	12%
1945-1964	2%	6%	8%	4%	3%	22%
1965-1982	5%	4%	7%	3%	2%	21%
post-1982	10%	3%	3%	8%	2%	26%
Total	22%	20%	22%	24%	13%	100%
Sample size						3,002

Table 2: Number of Occupied Dwellings by Age Band and Type, 2017 (Thousands)

Age of dwelling	Type of Dwelling
	Detached	Semi-detached	Terraced	Tenement	Other flats	Total
pre-1919	94	62	70	182	60	467
1919-1944	42	83	33	38	95	291
1945-1964	42	148	185	101	69	544
1965-1982	120	110	164	74	47	515
post-1982	256	79	83	189	39	646
Total	554	481	534	584	311	2,464
Sample size						3,002

19. The category ‘other flats’ includes houses that have been converted to flats (40,000), towers / slabs (64,000) and so-called “4-in-a-block” flats (207,000).

• “4-in-a-block” flats were commonly built as social housing between 1919 and 1965 (69% of all flats of this type fall in that age category).
• 85% of towers / slabs were built in the 1945 to 1982 period, again often as social housing.
• Converted flats are almost exclusively pre-1919 structures (92%), where a house has been divided into multiple residences.

2.1.1 Dwelling Size (Floor Area)

20. The size of the internal floor area has implications for the heating requirements of a dwelling. Larger dwellings require greater heat inputs and therefore cost more to heat. This has a direct impact on fuel poverty (see Chapter 4).

Figure 2: Mean Floor Area (m²) by Dwelling Type and Age, 2017

21. Pre-1919 dwellings tend to be larger than the other two age categories and this applies across all dwelling types with the exception of tenement flats which on average are comparable in size to more recently built ones (Figure 2). Detached and terraced houses built after 1919 are on average around three-quarters of the size of those built pre-1919. Semi-detached houses built after 1919 are on average around two thirds of those built pre-1919.

22. The overall average for post-1982 dwellings is somewhat higher compared to those built between 1919 and 1982. This is largely driven by differences in detached houses, which are both larger in size and more common in the post-1982 stock (see Table 2).

23. Rural dwellings are, on average, 44% larger than urban dwellings on average based on internal floor area, as shown in Table 3. The difference is smallest for dwellings built between 1919 and 1982 at 16%. Among older dwellings, rural properties are around 57% larger, while among the post-1982 stock the difference is 54%.

Table 3: Average Internal Floor Area (m²) by Urban/Rural Location, 2017

Dwelling Age	Location			Rural % larger
	Urban	Rural	All
Pre-1919	100	156	114	57%
1919-1982	86	100	88	16%
Post-1982	95	147	106	54%
All Age Bands	91	131	98	44%

2.2 Gas Grid Coverage and Rural/Urban Location

24. Approximately 17% of dwellings in Scotland are estimated to be outside the coverage of the gas grid^[6]. As shown in Table 4, the majority (92%) of urban dwellings are within the coverage of the gas grid, whereas over half (65%) of those in rural areas are not.

Table 4: Gas Grid Coverage Overall and by Urban/Rural Location, 2017

Gas Grid Coverage			Location
			Urban		Rural
	000s	%	000s	%	000s	%
On Gas Grid	2,038	83%	1,896	92%	148	35%
Off Gas Grid	425	17%	159	8%	260	65%
Total	2,464	100%	2,055	100%	409	100%
Sample size		3,002		2,341		661

25. Connection to the grid allows households to use gas for heating and hot water. Gas is currently the cheapest of the major commercial fuels, so gas grid access can have a strong effect on the cost of heating a home.

26. Figure 3 shows the number of dwellings in rural and urban areas by type.

Figure 3: Dwelling Types in Rural and Urban Areas (000s), 2017

27. Just over half (207,000) of all rural dwellings are detached, and 21% (85,000) are semi-detached. Only 9% of rural dwellings are flats; 36,000 in total.

28. The most common dwelling type in urban areas is the tenement flat (570,000), accounting for around 28% of urban housing. Around 58% of urban stock is detached, semi-detached and terraced houses, in total accounting for almost 1.2 million of the 2 million urban dwellings.

2.3 Heating Fuel

29. The primary heating fuel affects the cost of heating and therefore the energy efficiency rating of the dwelling and the risk of the occupants experiencing fuel poverty.

30. The relationship between the type of fuel used, the energy efficiency rating and fuel poverty will be explored further in later chapters. This section examines the distribution of dwellings in terms of the primary heating fuel used and a range of other characteristics, such as age and type of dwelling.

31. Overwhelmingly the most common heating fuel is mains gas: 79% of Scottish households (around 1.9 million) use mains gas for heating, 12% use electricity and 6% use oil.

Table 5: Primary Heating Fuel, Households (000s) and %, for All Stock and by Sector, 2017

	All Stock		Private		Social
Primary Heating Fuel	000s	%	000s	%	000s	%
Mains gas	1,937	79%	1,449	79%	488	78%
Electricity	292	12%	195	11%	97	15%
Oil	143	6%	143	8%	*	*
Communal Heating	32	1%	3	0%	29	5%
LPG bulk or bottled	30	1%	25	1%	5	1%
Solid mineral fuel	16	1%	10	1%	6	1%
Biomass	13	1%	13	1%	0	0%
Sample size	3,002		2,274		728

* denotes cases where attributes appear too rarely to provide an adequate basis for reporting. See section 7.1.6 for table conventions.

32. Gas and electricity are the main fuel types present in 93% of social housing. A further 5% (29,000 households) use some form of communal heating which is very uncommon in the private sector. Conversely, oil is rarely used to heat social housing but is the primary fuel of 8% of private dwellings.

33. 84% of dwellings built between 1919 and 1982 use gas as their primary heating fuel. In comparison, 73% of dwellings built after 1982 and 71% of dwellings built pre-1919 use gas. Older dwellings more commonly (17%) use other fuel types (than gas or electricity) while dwellings built post-1982 were most likely to use electricity (15%).

34. Primary heating fuel also varies by type of dwelling. As shown in Table 6, households living in detached houses are least likely to use mains gas for heating: 69% of them do, compared to almost 79% of households for Scotland as a whole and 85% of those households living in terraced houses. This is largely because less than a third (30%) of pre-1919 detached houses use gas as their primary heating fuel; 11% use electricity and 58% use some other fuel source. As shown in Figure 3 this is due to the higher proportion of detached dwellings in rural areas and Table 4 demonstrates that dwellings in rural areas are less likely to be within the coverage of the gas grid.

35. “Other” fuels (than gas or electricity) are most commonly used in detached houses across all age groups. Flats have the highest levels of electricity as primary heating fuel (18%), especially among post-1982 dwellings (27%).

Figure 4: Primary Heating Fuel by Age and Type of Dwelling, 2017 (per cent of dwellings in age/type category using fuel type)

Table 6: Primary Heating Fuel by Age and Type of Dwelling, 2017

Dwelling Type	Dwelling Age	Primary Heating Fuel			Sample size
		Gas	Electric	Other
All Dwelling types	All age bands	79%	12%	10%	3,002
	pre-1919	71%	12%	17%	512
	1919-1982	84%	10%	6%	1700
	post-1982	73%	15%	11%	790
Detached	All age bands	69%	6%	25%	824
	pre-1919	30%	11%	58%	147
	1919-1982	80%	4%	16%	314
	post-1982	75%	6%	19%	363
Semi	All age bands	84%	8%	7%	661
	pre-1919	72%	6%	21%	74
	1919-1982	87%	7%	6%	475
	post-1982	83%	14%	2%	112
Terraced	All age bands	85%	11%	4%	619
	pre-1919	75%	12%	12%	72
	1919-1982	87%	11%	2%	454
	post-1982	82%	13%	4%	93
Flat	All age bands	78%	18%	5%	898
	pre-1919	84%	14%	2%	219
	1919-1982	81%	14%	5%	457
	post-1982	65%	27%	8%	222

2.4 Household Type

36. In this report we describe households in terms of three main types which are derived from the more detailed classification used in the Scottish Household Survey^[7]:

• Families. These are households which contain at least one child aged under 16. The resident adults may be of any age.
• Older households. One- or two-member households which include at least one resident aged 65 or older.
• Other households. These are all other household types which are made up of adults only and have no resident children.

37. More details about the definitions are provided in section 7.9.2. This grouping was introduced in the 2015 Key Findings report and is different from the one used in previous reports, where the pensionable age for women was 60 and 65 for men. From 2015 onwards, 65 is adopted as the common age threshold for both men and women for older households reflecting the gradual increase in the state pension age for women.

38. There is a broad association between household types and the type of dwellings they occupy, as shown in Figure 5 and Table 7. While families and older households are more likely to live in houses (75% and 66% respectively), other households are more evenly split between houses and flats (56% and 44% respectively).

39. Families have the highest proportional occupancy of post-1982 houses: 26% of households with children live in post-1982 houses, compared with 13% of older households and 15% of other types of households. The highest occupancy of pre-1919 flats is observed among other types of households, 15%, compared to 6% for families and 6% for older households.

Figure 5: Proportion of Households in Each Dwelling Type and Age Band, 2017

Table 7: Proportion of Households in Each Dwelling Type and Age Band, 2017

Dwelling Type and Age Band		Older Households	Families	Other Households	All Household Types
Houses	Pre-1919	10%	9%	9%	9%
	1919-1982	44%	39%	32%	38%
	Post-1982	13%	26%	15%	17%
	Subtotal	66%	75%	56%	64%
Flats	Pre-1919	6%	6%	15%	10%
	1919-1982	16%	15%	19%	17%
	Post-1982	11%	5%	10%	9%
	Subtotal	34%	25%	44%	36%
Total		100%	100%	100%	100%
Sample size		1015	705	1,282	3,002

2.5 Tenure

40. Statistics on tenure in the SHCS are based on the achieved sample of dwellings in the physical survey and are not calibrated against figures produced as part of the Scottish Government Housing Statistics for Scotland^[8] publication or the Scottish Household Survey publication (which is based on a larger sample and different weighting methodology). For estimates of the total number of dwellings by tenure, readers are referred to the Housing Statistics for Scotland publication which uses information from social landlords’ returns which comprehensively cover the social housing sector and therefore provides more accurate estimates of the total stock.

41. In this section we explore data from the SHCS sample which provides more detailed information on the composition of each tenure type.

2.5.1 Household Type and Tenure

Figure 6: Proportion of Households in Each Tenure Group by Household Type, 2017

Note: Dashed lines represent the proportion of household type in Scotland as a whole.

42. There are some clear differences in household type across tenure, as shown in Figure 6.

43. Owner occupiers with mortgages are predominantly families (44%) and other households (49%), while those who own their properties outright are dominated by older households (61%) and other types of households (35%).

44. The majority of those who rent from private landlords (PRS) belong to other households (61%) and only 12% are older households. Around a quarter of renters in both the private (27%) and the social sector (25%) are households with children, which reflects their share in the national population.

2.5.2 Dwelling Type and Tenure

45. Figure 7 shows that rented properties in the Housing Association (HA) and the private rented sector are more likely to be flats. Flats account for 68% of Housing Association (HA) stock and 61% of dwellings rented from private sector landlords.

46. Owner-occupied dwellings are more likely to be houses: 80% of dwellings owned outright and 76% of those with a mortgage, compared to 49% of dwellings owned by Local Authorities, 32% of Housing Association stock and 39% of private rented properties are houses.

Figure 7: Proportion of Dwellings in Each Tenure Group by Age Band and Type of Dwelling, 2017

47. Almost all properties (92%) owned by Local Authorities were built between 1919 and 1982, while less than half (45%) of the Housing Associations stock was built in this period. 45% of Housing Association stock is more recent, built after 1982. By contrast, 41% of private rented sector dwellings were built before 1919 (Table 8).

Table 8: Proportion of Dwellings in Each Tenure Group, by Age Band and Type of Dwelling, 2017

Dwelling Age and Type		Owned	Mort- gaged	LA	HA	Private rented
Houses	Pre-1919	13%	12%	*	*	10%
	1919-1982	49%	35%	47%	17%	19%
	Post-1982	18%	29%	2%	15%	10%
	Subtotal	80%	76%	49%	32%	39%
Flats	Pre-1919	6%	9%	2%	10%	31%
	1919-1982	9%	9%	45%	28%	16%
	Post-1982	5%	7%	4%	30%	15%
	Subtotal	20%	24%	51%	68%	61%
Total		100%	100%	100%	100%	100%
Sample size		1104	797	439	289	373

2.6 Household Income Band

48. As we might expect, income and tenure are closely correlated. For social sector residents the distribution is skewed towards lower income groups, as shown in Figure 8, while households with mortgages have the largest share of higher income groups.

49. The distribution of households by income in the private rented sector (PRS) is broadly similar to that for outright owner occupiers. It is generally wider than the social housing sector, including significant shares of both higher and lower income band households.

Figure 8: Proportion of Households in Each Tenure Group by Weekly Household Income Band, 2017