BLDR vs CSL: How Builders FirstSource and Carlisle Companies Incorporated Compare (2026)

Same yardstick, side by side (as of July 2026). Valuation lined up like this is most meaningful for two names in the same corner of the market, which these are. Figures are approximate; verify before investing.

Reading it: BLDR is the cheaper of the two on forward earnings, but cheaper is not the same as better. Pair the valuation with growth (how far the forward P/E sits below the trailing P/E) and risk (beta) before you decide.

The metrics above tell you which is the marginally better business. The bigger risk for most people is not picking the slightly worse stock, it is over-concentrating. BLDR and CSL share themes, so owning both, or adding either to what you already hold, can quietly push a large share of your portfolio into one bet.

This is the part a generic comparison page cannot answer, because it depends on what you own. Connect your brokerage and Walnut shows your real, combined BLDR and CSL exposure, flags overlap with your existing positions, and tells you if adding one would tip you past a concentration you are comfortable with, read-only by default, with your login staying at your broker. Walnut is not an investment adviser.

Builders FirstSource (BLDR) is the largest US supplier of building materials, manufactured components, and construction services to professional homebuilders, remodelers, and contractors. It distributes lumber and a broad range of building products, and increasingly manufactures and sells higher-value value-added products: pre-assembled trusses, wall panels, millwork, doors, windows, and engineered components that save builders time and labor on the job site. The company operates a large network of distribution and manufacturing locations across the United States, giving it scale, local density, and purchasing power. Its results are tied to US residential construction, both new single-family and multifamily building and repair-and-remodel activity, which depend on housing demand, interest rates, and homebuilder confidence. Builders FirstSource has grown substantially through acquisitions, consolidating a fragmented industry, and uses strong free cash flow for aggressive share buybacks. Headquartered in Irving, Texas, it is a large-cap, cyclical building-products company whose value-added manufacturing mix and scale differentiate it from pure commodity distributors.

Full BLDR guide

Carlisle Companies Incorporated (NYSE: CSL) is a diversified manufacturer that, after years of portfolio reshaping, has become a focused supplier of building-envelope products that make commercial and residential buildings more energy efficient. It operates through two segments: Carlisle Construction Materials (CCM), which makes single-ply roofing membranes (EPDM rubber, TPO, and PVC), polyiso insulation, and metal roofing and wall systems, and Carlisle Weatherproofing Technologies (CWT), which makes waterproofing, air and vapor barriers, sealants, spray polyurethane foam, coatings, and related moisture-protection products. The company earns most of its revenue from commercial construction, and within that, a large share comes from re-roofing (replacing aging roofs), which is more stable than new construction because roofs wear out on a predictable cycle regardless of the economy.

Full CSL guide

Both fit overlapping themes, but they are not interchangeable. The useful comparison is which set of drivers and risks you want exposure to.

• BLDR drivers: Scale and consolidation; Value-added product mix.
• CSL drivers: Commercial re-roofing replacement cycle; Margin expansion and pure-play focus.

A faster-growing, richer-valued name usually swings harder, so it suits a longer horizon and a higher tolerance for volatility; a steadier, more cash-generative business suits a more conservative or income-minded investor. The honest test is which set of risks you could hold through a drawdown: Builders FirstSource is highly cyclical and tied to US housing: rising interest rates, falling affordability, or a construction slowdown reduce building activity and hit volumes and pricing. For CSL, carlisle's end markets are cyclical: commercial and residential construction activity is sensitive to interest rates, credit availability, and the broader economy, and a downturn in construction spending would pressure volumes.

Growth-minded investors who believe the theme has years to run tend to accept the richer multiple for more upside; value-minded investors lean toward the cheaper forward earnings and steadier profile. Pick BLDR if you believe its drivers more; CSL if you believe its. Many investors hold both, but since they share themes, that is a concentrated bet, not diversification. Decide deliberately and check overlap. For the full detail, see the BLDR and CSL guides.

BLDR. Builders FirstSource trades at a cyclical multiple that reflects its leverage to US housing. The valuation balances strong free cash flow, aggressive buybacks, and a higher-margin value-added mix against the volatility of construction volumes and lumber prices. Multiples tend to compress when housing sentiment weakens and expand when building activity and homebuilder confidence improve.

CSL. Carlisle trades around a low-20s trailing P/E, roughly in line with its own long-term historical median and typical for a high-margin, cash-generative industrial. Because a large part of its earnings power comes from resilient re-roofing demand and steady margin expansion, investors tend to focus on adjusted EBITDA margin, free cash flow, and the pace of buybacks rather than raw revenue growth, which can be lumpy with weather and construction cycles. The Q1 2026 revenue dip was driven largely by poor winter weather that limited roofing installation, while margins still expanded and management reaffirmed full-year guidance for low-single-digit revenue growth.

Headline figures (approximate, early 2026): BLDR shows revenue (ttm) ~$16-17 billion, operating margin ~low-double-digit percent (cyclical), net income (ttm) ~$1 billion, p/e (ttm) ~15-20x (cyclical); CSL shows revenue (ttm) ~$5.0 billion, q1 2026 revenue ~$1.05 billion (down ~4% year over year), q1 2026 adjusted eps ~$3.63 (up ~1% year over year), q1 2026 adjusted ebitda margin ~22.3% (up ~50 bps).

BLDR and CSL are related but distinct: same themes, different businesses and risks. Neither wins in the abstract; the right pick is whichever thesis you actually believe, sized so you are not over-concentrated in one theme. Walnut can show your combined BLDR and CSL exposure against your real portfolio. It is not an investment adviser.