In a recent article, NAHB analysis of government data found that new single-family and multifamily construction used a total of roughly $94.93 billion in building products in 2019.  Although the vast majority of the $94.93 billion was produced domestically, supporting jobs in the U.S. manufacturing sector, about 6.4 percent ($6.12 billion) was imported from other countries.  It may seem a relatively small number, but the 6.4 percent of the products that are imported can be important in plugging gaps in supply and preventing spikes in input prices.

Data for these estimates came primarily from the supply tables in the Input-Output Accounts generated by the U.S. Bureau of Economic Analysis (BEA).  To isolate the products used by new single-family and multifamily construction, NAHB relied on the most detailed version of the tables, with information on over 400 industry and product categories.  Because these tables are available only with a lag, NAHB adjusted them to 2019 levels using the changes in single-family and multifamily Residential Fixed Investment in BEA’s National Income and Product Accounts.  For convenience, and to make the results compatible with other data (particularly data available at the state level), NAHB aggregated the product categories slightly, up to 50 of the 4-digit categories in the North American Industry Classification System.  The 10 products that were used the most in new residential construction (based on dollar volume and this classification system) are shown below:

At the top of the list, as the graph shows, new residential construction used $11.71 billion of cement and concrete products in 2019, and $11.17 billion of architectural and structural metals.  Architectural and structural metals is a fairly diverse category that includes metal windows and doors, sheet metal ductwork, and rails and fencing.  After the top 2 categories, new residential construction also used $7.73 billion of petroleum and coal products and $6.95 billion of plastic products.  Petroleum and coal products include asphalt roofing and paving materials, as well as any petroleum based fuels and lubricating products.  Plastic products include plastic piping and plumbing fixtures, and polystyrene foam insulation.

Although individually accounting for smaller shares, when added together the three main categories of wood products (plywood and engineered wood products, sawn lumber and treated wood products, and “other” wood products) accounted for a little over $10 billion of the $94.93 billion in building products used in new residential construction in 2019.  And this does not even include the $5.37 billion in furniture and kitchen cabinets.  Also keep in mind that these estimates cover wood products used in residential construction last year, so they were purchased by builders or their subcontractors at 2019 prices—well before the latest surge in lumber prices began.

Detail on all 50 products used as inputs into residential construction in 2019—as well as supplemental information on where the products are manufactured and who decides which ones to buy—is available in the full article.

According to NAHB analysis of quarterly Census data, the market share of rental multifamily construction starts increased to 96% during the second quarter of 2020. In contrast, the historical low share of 47% was set during the third quarter of 2005, during the condo building boom. An average share of 80% was registered during the 1980-2002 period.

During the second quarter of 2020, there were only 3,000 condo multifamily units that started construction. There were 76,000 rental apartment starts. Condo construction has been weak since the end of the Great Recession.

An elevated rental share of multifamily construction is holding typical apartment size below levels seen during the pre-Great Recession period. According to second quarter 2020 data, the average per unit square footage of multifamily housing construction starts was 1,126, off from the post-recession high set at the start of 2015 (1,247 square feet). The median was 1,0391 square feet for the second quarter of the year.

Because the quarterly data are volatile, it is worth examining the numbers on a one-year moving average basis. For the second quarter of 2020, the one-year moving average for multifamily size was 1,109 square feet, while the median was 1,077. The current moving-average of median size is just 1% higher than the post-recession low, while the trailing average is now near post-recession low. Multifamily unit size may increase in the quarters ahead, as a market response to the coronavirus recession.