August 2026 RoMac Whole House Commodity Report: Building Material Costs Fall as Housing Demand Softens

RoMac Whole House Commodity Index, August 2026: $54,323. Down 1.5 percent from July. The Index tracks wholesale costs for a 2,200-square-foot wood-frame home with a concrete stem wall in Central Florida.

The RoMac Building Supply Whole House Commodity Index for August 2026 declined 1.7 percent to $54,323, reversing July's increase as lumber, OSB, trusses, drywall, and windows all moved lower. Vinyl and most manufactured products kept climbing.

The lower structural prices are a real opportunity for builders. They're also a demand signal, and you can't read one without the other.

New-Home Market Under Increasing Pressure

New single-family home sales in June came in at 628,000 units annualized, up 1.6 percent from May but 5.6 percent below June 2025. First monthly gain in three months, and most of it came from builders discounting to move homes, not buyers getting healthier. Inventory sat at 485,000 homes, or 9.3 months of supply, well above the four-to-six month range of a balanced market. Median new home price dropped to $398,300, down 2.7 percent year-over-year and the lowest since July 2025. The average sale price fell 6.5 percent to $475,400.

Single-family starts declined 0.2 percent in June to 895,000 annualized, running about 5 percent below the first half of 2025. Total starts were up on the month, but that was all multifamily. Single-family completions told a different story, jumping 6.6 percent to 964,000 annualized. More finished homes hitting the market while sales are soft means more unsold inventory sitting on builder books.

The forward picture from permits is also worth watching. Single-family permits in June declined 2.4 percent to 871,000 and are now down year-over-year, marking the fifth consecutive year of declining homebuilding permit activity nationally. Permits lead starts by 60 to 90 days, so June's weakness will show up in starts figures this fall.

Builder sentiment confirms it. The NAHB Housing Market Index fell to 34 in July, now below 50 for 27 consecutive months and below 40 for 15 straight, the longest such run since 2012. Thirty-seven percent of builders cut prices last month, up from 32 percent in May, with an average reduction of 6 percent. Sixty-three percent used sales incentives, the 16th consecutive month at or above that level. Builders aren't selling homes right now, they're working hard to move them and compressing margins in the process.

Florida: Active but Read the Numbers Carefully

Florida Realtors reported 26,036 existing single-family sales in June, up 9.3 percent year-over-year, with a median price of $432,000, an all-time high for Florida single-family homes. Condo and townhouse sales rose 14 percent, though that segment is sitting at 8.1 months of supply.

The year-over-year gain looks stronger than it is. June 2025 was a particularly weak month, and 2026 is tracking closer to 2023 than anything better. Single-family inventory sits at 4.5 months statewide, which sounds tight, but a good portion of that tightness comes from the rate lock-in effect. About 80 percent of existing mortgages are at or below 6 percent, and those homeowners aren't giving up that rate to buy something new at 6.7 percent. Several Florida markets, including Orlando and Lakeland, have seen inventory climb above pre-pandemic levels. Pending sales up 4.1 percent year-over-year in June is the most encouraging number in the Florida data.

Nationally, existing home sales fell 1.7 percent in July to 4.06 million annualized, per NAR's August 11 release, the second consecutive monthly decline though still up 0.7 percent year-over-year. NAR Chief Economist Lawrence Yun noted the market would be thriving if rates returned near 6 percent. Year-to-date existing sales are up 2.4 percent, which aligns with Florida's trend of modest improvement over a soft 2025 comparison.

Rates Are Higher and Still Not the Whole Story

The 30-year fixed averaged 6.69 percent the week of August 7 and eased slightly to 6.67 by August 13, running above where the MBA projected rates would be at this point in the year. Plan around upper-6 percent for the rest of 2026. There's a consistent threshold around 6.64 percent where buyer behavior shifts, and right now we're sitting just above it. Purchase applications are still running positive year-over-year, so the market hasn't shut down, but the momentum is gone.

Rates don't just discourage buyers, they disqualify them. A buyer with a stable income and no change in their financial picture can fail underwriting simply because the prevailing rate pushed their payment over the threshold. That falls hardest on first-time buyers, whose share of the market has already fallen to a record low of 21 percent. A rate cut helps at the margin. It doesn't solve a near-record inventory problem or close the price-to-income gap that's been widening since 2019.

Major Commodity Price Movers: Last 30 Days

Southern Pine reversed hard: 2x6’s dropped 20.9 percent, 2x4’s are down 17.2 percent, borate-treated Pine fell 14.8 percent, and 2x12 declined 4.0 percent. Trusses followed pine down and dropped 8.6 percent, OSB dropped 7.7 percent, drywall came down 2.4 to 2.9 percent depending on the board, and windows fell roughly 3 percent. These are the categories that drove the Index lower and where builders have a real opportunity right now.

Spruce was a different story. Studs fell only 0.7 percent, 2x4 spruce was up 0.6 percent, 2x6 up 3.6 percent, while CDX plywood is up 0.9 percent. Southern Pine has no import tariff and responds directly to weak domestic demand. Spruce comes mostly from Canada and is still insulated by tariff structures. That gap may narrow soon: revised antidumping and countervailing duties on Canadian softwood are expected to take effect this month, reducing the combined tariff from roughly 35.2 percent to approximately 25.9 percent. If those rates hold, spruce should see some cost relief. For now, if you have flexibility on species, Southern Pine is still the better buy.

Madison's Lumber Price Index put framing lumber at $558 per thousand board feet as of August 7, down 9.4 percent over the past month and 11.4 percent year-over-year on a futures basis. Construction spending on lumber-intensive single-family housing fell 3.3 percent year-on-year in June. This is the second significant lumber correction of 2026, and it's driven by the same weak single-family conditions visible throughout this report.

Manufactured products went the other way. Vinyl soffit and J-channel each rose 6.4 percent. Sill seal posted the largest single-item increase in the Index at 15.7 percent. These products are tied to petroleum and freight costs that have eased from 2026 peaks but remain above pre-conflict baselines. Part of what's keeping supply tight on steel, aluminum, and energy-intensive materials is demand from data center construction, which has been consuming those same supply chains at a pace the residential market can't compete with. The Iran ceasefire MOU hasn't shown up in wholesale pricing yet.

Outlook and Guidance for Builders

Lock in structural material pricing now. Southern Pine, OSB, trusses, drywall, and windows are all cheaper than last month. If you have starts in the next 30 to 45 days, secure your quotes before this window closes. Quote validity windows have been shrinking, with some suppliers now repricing every one to two weeks rather than holding prices for 30 to 60 days. Get it in writing and move on it.

Watch the Canadian tariff revision. If the revised duties on Canadian softwood take effect as expected this month, spruce pricing should ease and the gap with Southern Pine will narrow. Don't lock in species-specific assumptions without checking where spruce sits after the adjustment lands.

Be cautious about spec construction, meaning homes started without a signed contract or a well-qualified buyer in process. Permits are falling, starts are trending lower, and completions are rising. That combination means more finished homes competing for the same buyers. Price cuts become likely, the material savings disappear, and you've carried the cost the whole time.

Watch manufactured products individually. The overall Index is down but vinyl, sill seal, and other petroleum-dependent lines are not. Don't let a favorable Index number give you a false read on your actual job cost. Keep escalation language in your contracts. Lumber went from double-digit increases in July to double-digit declines in August. It can go either way fast.

The RoMac Building Supply Whole House Commodity Index is based on wholesale costs of the base components to build a 2,200-square-foot wood-frame home with a concrete stem wall in Central Florida. The Index includes foundation, metal, concrete, block, stucco, cement, wood framing, siding, sheathing, trusses, roofing, drywall, insulation, windows, doors, trim, garage doors, and most building hardware. It does not include decor, electrical, plumbing, mechanical, landscaping, or labor. Because the Index uses current wholesale costs, it serves as a leading indicator of the direction of residential building material prices over the next 30 to 45 days.

Jake Trapp is the President of RoMac Building Supply in Central Florida.

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