S&P Global Construction PMI

What is S&P Global UK Construction PMI?

The S&P Global UK Construction PMI is a monthly survey of purchasing managers who buy materials and services for builders. S&P Global sends questionnaires to around 150 UK construction firms, grouped by workforce size to reflect GDP shares, with records running since April 1997. Each firm reports rise, flat or fall versus the prior month, so the survey signals direction, not the official ONS output level.

The headline Total Activity Index tracks the total volume of activity in a 0 to 100 gauge where 50 means no change. Above 50 means growth and below 50 means contraction, each measured against the previous month.

When is it released and what happens each release?

Replies are collected in the second half of each reference month and describe change against the prior month. Results appear early in the next month under embargo until 09:30 UK time, with the exact day shifting around weekends and holidays. Each release shows the headline index with its history chart, three activity splits, new orders, jobs, buying, prices, delivery times and expectations. An economist comment explains the move, published answers are never revised, but seasonal factors can revise the adjusted series.

What moves S&P Global UK Construction PMI?

The headline follows site activity, fresh demand, staffing, buying volume and cost pressure.

• Housing: change in house building activity.
• Commercial: change in commercial building work.
• Civil engineering: change in infrastructure work, including renewables and major projects.
• New orders: change in fresh project starts and order books.
• Employment: change in staffing levels.
• Input prices: change in purchase costs, where above 50 means rising costs.

The September 2024 release was published 4 October 2024. In September 2024 the headline posted 57.2, up from 53.6 and above 50 for a seventh straight month, the fastest growth in 29 months. All three splits accelerated as civil engineering hit 59.0 on renewables and major projects, commercial reached 55.2 and housing rose to 54.3. New orders hit the fastest pace in 2.5 years and buying neared its fastest since early 2022, yet delivery times shortened on vendor stocks.

Input prices rose for a ninth month at the fastest pace since May 2023, while expectations stayed upbeat but slipped to the weakest since April.

How is S&P Global UK Construction PMI calculated?

1. Collect answers: each firm reports whether the variable rose, held steady or fell versus the prior month.
2. Apply diffusion formula: it equals H plus 0.5 times U, where H is the higher share and U is the unchanged share.
3. Read the scale: scores run from 0 to 100, with 50 marking no change, above 50 signaling growth and below 50 signaling contraction.
4. Seasonally adjust: raw indices are smoothed for normal calendar effects, and the headline is the adjusted total activity index.
5. Worked example: if 30% report higher, 50% report no change and 20% report lower, the index is 30 plus 0.5 times 50, or 55.0.

Key point: the headline is its own survey index, not a weighted mix of parts. It matches the Manufacturing Output Index and the Services Business Activity Index, not the headline manufacturing PMI, so weak housing alone does not refute it.