House prices in 'SA1 8', St Thomas

This article reveals price per square foot data and various charts to help you understand current housing market in 'SA1 8' (St Thomas, Swansea) - statistics were last calculated on 01 November 2024.

Defining 'SA1 8'

This analysis is limited to properties whose postcode starts with "SA1 8", this is also called the postcode sector. There are no official postcode sector names so I've just labelled it SA1 8, St Thomas. It is shown in red on the map below.

Want to change geography?

You can click on the map above to change to a neighbouring sector, or you can use the search form below.

Price per square foot

Knowing the average house price in SA1 8 is not much use. However, knowing average price per square foot can be quite useful. Price per sqft allows some comparison between properties of different size. We define price per square foot as the sold price divided by the internal area of a property:

£ per sqft = price ÷ internal area

For example in September 2024, 3, Gelli Street, St Thomas, SA1 8NJ sold for £137,950. Given the internal area of 1,033 square feet recorded on the EPC, the price per sqft is £137,950 ÷ 1,033 sqft = £133.

England & Wales have been officially metric since 1965. However house price per square foot is prefered by some estate agents and those of sufficiently advanced age ;-). It is a huge pain to code the automatic conversion for square meters to square feet for all the graphs and charts on SA1 8 and elsewhere. All the conditionals turn my tidy code for into spaghetti. I will get around to it at some point, but for now you can just divide everything by 10 in your head, move a decimal place and you'll be close enough. If you want to be more precise 1 sqm = 10.76391 sqft.


Distribution of £ per sqft for 'SA1 8' vs 'SA1'

The chart above is called a histogram, it helps you see the distribution of house price per sqft in SA1 8 To make this chart we put all the sales data into a series of £ per sqft 'buckets' (e.g. £176 to £185, £185 to £195, £195 to £204 etc...) we then count the number of sales with within in each bucket and plot the results. The histogram is based on 203 sales that took place in SA1 8, St Thomas, Swansea in the last 24 months.

Generate a custom histogram like the one above but based on your own criteria.

You can see the spread of prices above. This is because although internal area is a key factor in determining valuation, it is not the only factor. Many factors other than size affect desirability; these factors could be condition, aspect, garden size, negotiating power of the vendor etc.

The spread of prices will give you a feel of the typical range to expect in SA1 8, St Thomas. Notably, only 25% of properties that sold recently were valued at more than £196 sqft. For anything to be valued more than this means it has to be more desireable than the clear majority of SA1 8 homes.


Box plot of £ per sqft for SA1 8

Tip: click on the chart to see the values.


The chart above is called a boxplot (or a box-and-whisker plot). Box plots, like histograms, are used to graphically represent the distribution of data, showing the central tendency, spread of the distribution. In the context of £ per square foot property price distributions, box plots represent the variation in property prices within a geographic area e.g. St Thomas. The chart above shows a boxplot for 'SA1 8' as well as the 'SA1' postcode district.

  • Median: The horizontal line inside the box represents the median (£ per square meter). This is the midpoint of the data, meaning 50% of the prices are below this value, and 50% are above. The middle price per square foot in 'SA1 8' is £143.
  • Interquartile Range (IQR): The box spans from the 25th percentile (Q1) to the 75th percentile (Q3). This is the range where the middle 50% of the data lies, giving a good indication of the typical price spread. Of the 203 transactions in SA1 8, St Thomas half were sold for between £118 and £196 per square foot.
  • Whiskers: In our case, the whiskers extend from the 9th percentile (at the lower end) to the 91st percentile (at the upper end), This provides a slightly broader view of the distribution by including the middle 82% of records. The whiskers capture most of the variation but exclude extreme outliers caused by data errors in recording sold house prices or internal area.
  • 'n=' is the number of property transactions the box plot is based on; 203 for SA1 8, St Thomas.
  • Property price map for St Thomas

    Have a look at the interactive price map I created for myself. Use it to explore 'SA1 8' house prices all the way down to individual property plots.

    Property price heatmap for St Thomas
    House price map for St Thomas

    St Thomas house price forecasting

    I cannot tell what house prices will do in the future and don't believe anyone who says they can. However we can plot price trends, I have done this in the chart below for SA1 8 (St Thomas) compared with the wider postcode district of SA1. You can extrapolate from this based on your own views on future interest rates, inflation and other factors.


    House price index for SA1 8

    Tip: click on the legend items to show/hide different lines


    Download house price index as CSV (premium users only).

    The chart above shows changes in 'SA1 8' property prices over the last 20 years. The index is calculated from the average price paid per sqft for property in SA1 8 and is set to 100 in 2004. I'm comparing the trends for SA1 8,St Thomas with the wider postcode district of SA1 What is more interesting is to look at the difference between flats and houses, even those in the same area follow a very different trend, to get a robust enough sample size to see this we need to zoom out and look at house price trends for the entire Swansea local authority.

    The dashed lines show nominal house price changes, the solid lines show the same data adjusted for inflation. Economists call this the 'real' price change. You have to take inflation into account when comparing prices over time. It's calculated using the formula:

    Real Rate of Return = (1 + Nominal Rate) ÷ (1 + Inflation Rate) – 1
    In this formula, the nominal rate is the rate of change before any adjustments, and the inflation rate is taken from the Consumer Price Index. The real rate of return is a more accurate measure of change in value, because £1 today does not have the same buying power as £1 in the past. For example, if a savings account pays an interest rate of 3% per year and the inflation rate is 5% per year, the real rate of return is -2%. This means that the investment's value is shrinking by 2% each year.

    Historic returns for SA1 8
    SA1 8 sector SA1 district
    Nominal Real Nominal Real
    20 yr per annum 2.8% 0.1% 2.4% -0.3%
    20 yr total 73.7% 2.9% 59.9% -5.3%
    10 yr per annum 3.9% 1.1% 2.9% 0.1%
    10 yr total 46.5% 11.3% 33.5% 1.4%
    5 yr per annum 2.2% -1.9% 3.1% -1.0%
    5 yr total 11.2% -8.9% 16.3% -4.8%
    1 yr per annum -0.1% -4.1% 0.5% -3.5%
    1 yr total -0.1% -4.1% 0.5% -3.5%

    This table complements the house price index chart above, presenting the data in a more detailed format. It breaks down the information into 20-year, 10-year, 5-year, and 1-year periods, further categorized by property type. For each period, we display both a per annum rate of change and a total rate of change.

    The total rate of change represents the overall change over the entire period. The formula for total return is:

    Total return = (Index at end of period ÷ Index at start of period) - 1

    The per annum rate of change is the annualized rate of change over the period. This is equivalent to the annual bank savings rate you would need to achieve the same total return over the given period. This annualized return is also known as the Compound Annual Growth Rate (CAGR). The formula for CAGR is:

    CAGR = (1 + Total return) ^ (1 ÷ Number of years) - 1

    Some specific examples:

    • Over the past 20 years, SA1 8 sector have seen a 0.1% annual change when adjusted for inflation. This translates to a total change of 2.9% in real terms.
    • Over the past 5 years, SA1 8 sector have seen a -1.9% annual change when adjusted for inflation. This translates to a total change of -8.9% in real terms.

    Most recent SA1 8 sales

    For the most recent sales activity, rather than a summarized average, it is better to see the underlying data. This is shown in the chart below, where blue dots represent individual sales, click on them to see details. If there is an obvious trend you should be able to spot it here amid the noise from outliers.


    Tip: hover over dots to see details


    Street level data

    Street Avg size Avg £sqft Recent sales
    Windmill Terrace, St Thomas, SA1 8D 84 sqm £128 16
    Marcroft Road, St Thomas, SA1 8N 77 sqm £215 15
    Port Tennant Road, St Thomas, SA1 8J 101 sqm £114 13
    Ysgol Street, St Thomas, SA1 8L 116 sqm £128 12
    Yr Hafan, St Thomas, SA1 8R 130 sqm £245 11
    Danygraig Road, St Thomas, SA1 8L 112 sqm £115 11
    Danygraig Road, St Thomas, SA1 8N 93 sqm £119 11
    Grenfell Park Road, St Thomas, SA1 8E 72 sqm £134 10

    Search for your street here.

    Nearby geographies

    The table below shows how 'SA1 8' compares to the other postcode sectors in SA1.

    Sector Lower quartile Median Upper quartile Sales in last 2yr
    SA7 9 Llansamlet £158 sqft £202 sqft £229 sqft 262
    SA1 8 St Thomas £118 sqft £143 sqft £196 sqft 203
    SA1 7 Bonymaen £134 sqft £173 sqft £229 sqft 156
    SA1 6 Swansea £104 sqft £129 sqft £161 sqft 307
    SA1 5 Swansea £145 sqft £156 sqft £180 sqft 29
    SA1 4 Swansea £124 sqft £145 sqft £168 sqft 105
    SA1 3 Swansea £150 sqft £181 sqft £214 sqft 96
    SA1 2 Landore £114 sqft £141 sqft £159 sqft 130
    SA1 1 Maritime Quarter £195 sqft £234 sqft £277 sqft 134
    SA10 6 Skewen £135 sqft £191 sqft £238 sqft 264

    Raw data

    Our analysis of SA1 8 is derived from what is essentially a big table of sold prices from Land Registry with added property size information. Below are three rows from this table to give you an idea.

    Address Paid sqft £/sqft
    3, Gelli St, St Thomas, Swansea £137,950
    Sep-2024
    1,033 133
    32, St Leger Crescent, St Thomas, Swansea £66,250
    Sep-2024
    936 70
    25, Osterley St, St Thomas, Swansea £134,000
    Sep-2024
    936 143

    See the entire list of all sales in SA1 8 here.

    About

    I created HouseMetric because I wanted to see this data and analysis myself, I also wanted to teach myself to build a website. Please give me feedback or spread the word about it. I'm constantly tinkering and adding more stuff to it.