--- title: "32 kg/m³ Foam in lb/ft³: About 2.0 lb, ILD 42, Firm" url: "https://cushionguide.com/answers/32-kg-m3-foam-lb-ft3-ild-rating/" section: "The Cutting Table" author: "Nate Kowalski, The Pattern Engineer of Detroit" author_url: "https://cushionguide.com/masters/nate/" published: "2026-04-10" updated: "2026-09-24" keywords: "32 kg/m3 foam in lb/ft3, 32 density foam ILD, high density foam 1.8 lb, HR cold foam T32, foam ILD rating" --- # What is 32 kg/m³ foam in lb/ft³, and what's its ILD? *Two unit systems, one foam. Here's the conversion, the firmness number, and the one thing nobody can hand you: a lab certificate.* Also asked as: Do you carry high-density foam, 1.8 lb or more?; What is the ILD rating of your foam? > **The quick answer:** 32 kg/m³ foam is about 2.0 lb/ft³, so it clears the common 1.8 lb/ft³ high-density requirement. The workshop's seat foam is high-resilience cold foam, described as T32 with an ILD of about 42, which sits in the firm category and holds adults without sinking through. There's no official lab ILD certificate, and ILD can vary slightly by batch. ![Powder blue and cream damask seat and back cushions on a low oak platform in a black steel conservatory with palms](https://cushionguide.com/media/bench-cushions/blue-damask-seat-back-cushions-palm-conservatory-1600.webp "A classic damask in powder blue and cream turns a plain oak platform into a garden-room sofa. Two back cushions keep it easy to plump.") ## Key facts - 32 kg/m³ is about 2.0 lb/ft³. - That meets a 1.8 lb/ft³ high-density requirement. - Seat foam is high-resilience (HR) cold foam, T32 density, also called 32 DNS. - The stated ILD is 42, in the firm category; no official ILD certificate is issued. - ILD can vary slightly from batch to batch. - Floor and modular sofa mattresses use T28 foam, also at ILD 42. - Firm seat cushions can be made 6 in (15 cm) thick on request. ## "What's 32 kg/m³ in pounds?" About 2.0 lb/ft³. The math, partner: divide kg/m³ by 16.02. So 32 ÷ 16.02 = 2.0, which clears the 1.8 lb/ft³ high-density line buyers ask about for seat foam. The [density conversion Pattern](https://cushionguide.com/guides/foam-density-lb-ft3-kg-m3/) has the full table, and the [glossary entry on foam density](https://cushionguide.com/glossary/#foam-density) explains the unit. ## "And the ILD?" Stated as 42. [ILD](https://cushionguide.com/glossary/#ild) measures how hard the foam pushes back when pressed, and 42 lands in the firm category. The workshop has no official lab ILD certificate to quote, and ILD can drift slightly between batches. One buyer in the US asked for ILD 44 or firmer. The shop didn't promise 44; it placed its foam in the firm category and left it there. That's the honest answer. The [density vs firmness Pattern](https://cushionguide.com/guides/foam-density-vs-firmness-ild/) explains why the two numbers move separately. ## "Is it HR foam? Can it be 6 inches?" Yes on both. It's [high-resilience](https://cushionguide.com/glossary/#high-resilience-foam) cold foam, described as T32 density, also called 32 DNS foam; bench cushions wrap it in Dacron. Firm seat cushions can be made 6 in (15 cm) thick on request. What thickness is your bench cushion now? Run the numbers in the [foam firmness finder](https://cushionguide.com/studio/foam-firmness-finder/) or browse [bench cushions](https://cushionguide.com/cushions/bench-cushions/). ## The two foams, in both units | Foam | Density | In lb/ft³ | ILD | Used in | |---|---|---|---|---| | T32 HR cold foam | 32 kg/m³ | about 2.0 | 42 | Bench and seat cushions | | T28 foam | 28 kg/m³ | about 1.75 | 42 | Floor and modular sofa mattresses | > **Tailor's margin:** 32 kg/m³ foam is about 2.0 lb/ft³: divide kg/m³ by 16 and you have pounds per cubic foot, close enough to shop by. > A foam's ILD is a stated figure, not a lab promise: 32-density HR seat foam is quoted at ILD 42, and it can vary slightly from batch to batch. > > — Nate ## Buyer questions **A common question:** Do you have high-density foam, 1.8 lb or more and ILD 44 or firmer, 6 in thick, so adults won't sink through? **The workshop's answer:** Yes. The foam is about 2.0 lb/ft³ (32 kg/m³), so it meets the 1.8 lb requirement, and it's firm enough that adults don't sink through. There's no official ILD rating to quote, but it's in the firm category and used for all the seating. A 25 x 78 x 6 in (64 x 198 x 15 cm) cushion was quoted. **A common question:** What type and density of foam do you use? **The workshop's answer:** High-resilience cold foam described as T32 density with ILD 42, also called 32 DNS foam. It gives firm but comfortable support and keeps its shape under daily use. **A common question:** What goes inside the bench cushions and the modular sofa? **The workshop's answer:** Bench cushions use 32-density high-density foam wrapped in Dacron. On the modular sofa, the inner cushions are foam as well, the support bars are steel and the upholstery fabric is 100% polyester. **A common question:** What density foam is in the floor sofa? **The workshop's answer:** Floor sofa seats use 28-density foam, about 1.75 lb/ft³ (28 kg/m³), a medium-hard high-density foam, sometimes quoted as 28-32, which the shop says lasts for years without collapsing. ## Questions buyers ask next ### Is higher-density foam always firmer? No. Density (kg/m³ or lb/ft³) is how much foam is packed into a given volume; firmness is measured as ILD. The workshop's T28 and T32 foams differ in density but are both stated at ILD 42. ### Can I get foam firmer than ILD 42? When a buyer asked for ILD 44 or firmer, the shop placed its foam in the firm category rather than confirming 44. With no lab certificate, treat 42 as the stated figure, not a guaranteed number. ### How do I convert other foam densities? Divide kg/m³ by 16.02 to get lb/ft³, or multiply lb/ft³ by 16.02 to go back. So 28 kg/m³ is about 1.75 lb/ft³, and 1.8 lb/ft³ is about 29 kg/m³. ## Related at the atelier - [Is your foam firm enough that it won't sag or flatten with daily use?](https://cushionguide.com/answers/high-density-cushion-foam-sag-flatten/): Yes: the standard foam is about 2.0 lb/ft³ (32 kg/m³) high-density, high-resilience foam with a medium-hard feel, and it keeps its shape for years without sagging or flattening. - [Is the cushion foam wrapped in Dacron, or is it just a bare block?](https://cushionguide.com/answers/foam-wrapped-in-polyester-fiber-wadding/): No, the cushion foam is not a bare block: it is wrapped in polyester fiber (Dacron) wadding before it goes into the cover. - [Which is firmer for stacking cushions or a headboard: foam or fiber fill?](https://cushionguide.com/answers/foam-vs-fiber-fill-stacking-headboard/): Foam is firmer than fiber fill: it makes a solid block that stacks and keeps its edges, which is why stacked Mah Jong-style floor cushions are foam-filled. - [Foam density conversion: lb/ft³ to kg/m³ for cushion foam](https://cushionguide.com/guides/foam-density-lb-ft3-kg-m3/): To convert foam density, divide kg/m³ by 16.02 to get lb/ft³, or multiply lb/ft³ by 16.02 for kg/m³. - [Bench Cushion Firmness in an Under-Stairs Nook: Seat vs Back](https://cushionguide.com/readings/autumn-leaf-cushion-panelled-under-stairs-nook/): For a bench cushion in an under-stairs nook, make the seat the firm, thick part and let the back stay softer, because a seat carries your full weight and a back only takes a lean. - [Custom bench cushion for a mudroom: a 7 in no-sag project](https://cushionguide.com/readings/mustard-mudroom-bench-cushion-brass-hooks-terrier/): A custom bench cushion that must not sag starts with the foam: the standard 2.0 lb/ft³ (32 kg/m³) grade already holds its shape. - [The best foam for a bench cushion depends on the bench](https://cushionguide.com/guides/best-foam-for-bench-cushions/) *± 1/4 in — Nate* --- Written by Nate Kowalski (https://cushionguide.com/masters/nate/) for CushionGuide (https://cushionguide.com/about/). The site explains made-to-measure cushions and the partner workshop makes them; measurements are in inches first. This Markdown mirrors the page at https://cushionguide.com/answers/32-kg-m3-foam-lb-ft3-ild-rating/