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Treated Lumber vs. Steel Framing: Why Colorado Homeowners Prefer Wood Decks

Thinking about adding a new deck to your home in Castle Rock, Aurora, or Highlands Ranch? You’re not alone! Many Colorado homeowners are dreaming of a beautiful outdoor space to enjoy our sunny days and crisp evenings. One big question that comes up when planning a deck is: What kind of frame should support it? In deck construction, the frame is the backbone. It holds up the decking boards and keeps everything sturdy and safe. The two most popular options are pressure-treated lumber (wood) and steel framing.

In this friendly guide, we’ll compare treated lumber and steel framing for decks. We’ll look at cost, durability, aesthetics, ease of installation, and maintenance. Most importantly, we’ll explain why treated lumber is often the better choice for homeowners in Colorado’s unique climate. Whether you’re in Parker, Lone Tree, Centennial, Littleton, or Franktown, we’ve got insights tailored for you. Let’s dive in and help you make the best decision for your dream deck!

Understanding Deck Framing Materials

Before we compare, let’s clarify what we mean by treated lumber vs. steel framing:

  • Treated Lumber Deck Framing: This usually means pressure-treated wood (often pine or fir) that has been infused with preservatives to resist rot and insects. It’s the traditional way to build a deck frame. The wood posts, beams, and joists form a strong foundation for the deck. In Colorado, you might also see builders use naturally durable woods like cedar or redwood for framing, but pressure-treated pine is very common due to its affordability and resistance to moisture and pests.
  • Steel Deck Framing: This is a newer alternative using galvanized steel beams and joists instead of wood. Steel framing systems (like those by Fortress or Trex Elevations) are specifically engineered for decks. The pieces are usually light-gauge steel that is coated to prevent rust. The frame is assembled with screws or brackets, creating a metal skeleton under the deck boards.

Both materials ultimately do the same job: they keep your deck sturdy and level. However, they have some key differences. Let’s explore those differences and see why treated lumber often comes out on top for homeowners in our area.

Cost Comparison: What’s Easier on the Wallet?

One of the first things most homeowners consider is cost. Building a deck is an investment, and framing materials can significantly affect the overall price.

  • Up-Front Cost of Treated Lumber: Pressure-treated wood is generally more budget-friendly initially. For the same size deck, a wood frame will typically cost less in materials than a steel frame. For example, one estimate found that for a ~300 square foot deck, a traditional pressure-treated wood frame could save around $2,500 to $5,000 compared to a steel frame of the same size. That’s a substantial difference! Wood prices can fluctuate, but even with recent lumber price spikes, pressure-treated lumber is still usually the more economical choice up front.
  • Up-Front Cost of Steel Framing: Steel deck framing materials tend to be more expensive per square foot. The steel itself, plus specialty screws and connectors, can drive up the price. On top of that, not every contractor has steel framing readily in stock, so it might need special ordering. Steel’s higher material cost can add thousands of dollars to a project’s base price. As a homeowner, you might wonder if that higher cost is worth it.
  • Long-Term Value: Advocates of steel framing will point out that steel might save money in the long run because it can last a very long time without needing replacement. It’s true that a galvanized steel frame won’t rot, and it could outlast the wood decking boards above it. However, pressure-treated wood can also last for decades when the deck is built well and maintained. In practice, many Colorado homeowners replace or update their decks for style or surface wear long before the frame has completely failed. So, the wood frame often serves faithfully for the life of the deck. Plus, any potential long-term savings with steel are harder to realize if you plan to move or remodel in the meantime. For many, the lower up-front cost of wood is a decisive factor.

Bottom Line on Cost: If you’re budget-conscious or looking to get the most deck for your dollar, treated lumber is the winner in terms of initial cost. It’s the affordable choice that leaves you more money for nice upgrades like custom railing or beautiful decking boards. Steel framing is an investment that might pay off over very many years, but for most homeowners in Castle Rock or Littleton who want a great deck now, wood makes financial sense.

Durability and Strength in Colorado Weather

Colorado’s climate can be tough on outdoor structures. We get intense UV sun at high altitude, dry spells, sudden rain or snow, and big temperature swings between day and night. So, how do wood and steel deck frames hold up in these conditions?

  • Durability of Treated Lumber: Pressure-treated lumber is designed to resist decay. The treatment helps the wood fend off rot during wet weather and discourages termites or other pests. In our dry Colorado air, rot is less of a concern compared to humid climates, which is good news for wood. However, the dryness and UV exposure here can cause untreated wood to crack or warp over time​. The good news is that treated lumber, especially when it’s high quality and properly sealed, can handle these conditions well. Many decks in Colorado built with cedar or premium treated pine have lasted 20 years or more with routine care. Wood has a bit of natural flexibility, which means it can expand and contract with temperature changes without losing structural integrity. Proper construction techniques – like using galvanized hardware, adding joist protection tape, and keeping the wood sealed – will greatly extend a wood frame’s lifespan in our climate. In fact, CA Carpentry always uses top-grade framing lumber and protective measures to ensure your deck frame is built to last through many Colorado winters and summers.
  • Durability of Steel Framing: Steel is incredibly strong and not susceptible to rot, bugs, or wood decay. A steel frame, if properly galvanized and installed, won’t warp or twist with moisture. It will stay straight through hot and cold cycles, and it can definitely handle heavy snow loads. This is why some say a steel frame might last longer than the deck boards themselves. However, steel is not invincible. Its main enemy is rust. In Colorado’s climate, rust isn’t as immediate a threat as in a humid coastal area, but any scratch in the protective coating of a steel frame can eventually lead to corrosion if water finds it. Homeowners must ensure that cut ends or drill holes in steel framing are painted or treated to prevent rusting. If you live in a place like Franktown or Parker, you know we can get spring snowstorms and summer thunderstorms. Steel won’t mind the moisture, but if you ever do have a rust issue, it’s much harder to fix a steel beam than a wood one. Treated lumber, on the other hand, can sometimes be reinforced or patched more easily if a section has an issue years down the line.
  • Strength: Both wood and steel provide plenty of strength for a deck when properly engineered. Treated lumber has been the standard for decades and can support heavy loads – from your family barbecue party to that new hot tub (with proper design). Steel is actually lighter for the same strength and can span longer distances without support posts. This means a steel frame might use fewer posts or beams, potentially giving more open space beneath a high deck. But for a typical backyard deck in Aurora or Centennial, the spans with wood framing are usually just fine. City building codes in Colorado ensure that a wood-framed deck, built to code, will hold up to snow and people safely. CA Carpentry’s team in Castle Rock designs wood decks with all the necessary supports, so strength is not an issue. In short, treated lumber is plenty strong for residential decks, and it’s a proven material in Colorado construction.

Bottom Line on Durability: Steel is extremely durable and strong – there’s no denying that. However, treated lumber is tried-and-true for Colorado decks. It’s tough enough to withstand our weather when built right. With a bit of maintenance, a wood frame can last for many years, giving you a safe and sturdy deck. You won’t be worrying about your deck’s strength whether it’s built on wood or steel, as long as you have a quality builder. It’s more about how each material handles the elements over time. For most homeowners, a treated lumber deck frame offers durability that meets their needs without the extra cost of steel.

Aesthetics: Warmth of Wood vs. Modern Metal Look

While the frame of your deck isn’t usually front-and-center like the decking boards or railing, aesthetics still matter. This is especially true if you have a high deck where the framing is visible from underneath, or if you plan to leave parts of the frame exposed in the design. Let’s consider how wood and steel compare in look and feel:

  • Natural Appeal of Wood: Wood simply has a warm, natural look that many homeowners in Colorado love. After all, many houses in areas like Littleton and Highlands Ranch feature wood trim, wood fences, or rustic touches that blend with the natural surroundings. A wood deck frame, even though mostly hidden, can complement this aesthetic. If any part of the frame is visible (such as the support posts, or the beam along the edge of the deck), it can be stained or painted to match the rest of the deck. Many people appreciate that wood has a traditional appearance that feels at home in our Colorado landscapes. Picture a rustic mountain-style home in Franktown with a beautiful deck – a wood structure fits right in with the pine trees and red rocks. Steel, by contrast, might look a bit out of place in that setting.
  • Sleek Look of Steel: Steel deck frames are often powder-coated in dark colors (black or gray). They have a sleek, modern look and clean lines. For some contemporary home designs, that industrial hint could be appealing. If you stand under a steel-framed deck, it does look crisp and uniform. Some homeowners say it’s an interesting contrast to have steel bones with wood or composite deck boards on top. However, if your home style is traditional or your neighborhood in Parker leans toward a classic suburban look, a black steel frame under your deck might not be the aesthetic you want. It could draw attention where you’d rather have the frame blend in. With wood, you can easily attach fascia boards or wrap columns in decorative wood to enhance the look. Steel can be painted, but you’re generally limited to its modern, metallic appearance.
  • Comfort and Feel: There’s also something psychological about knowing your deck is built from wood – the same material as the surface you walk on. It just feels solid and familiar. Colorado homeowners who have been around decks all their lives might find comfort in the tried-and-true wood construction. Steel is unquestionably solid, but it gives an “industrial” vibe. If you’re aiming for a cozy, Colorado lodge feel on your back deck in Castle Rock, you’re probably envisioning timber, not steel beams.

Bottom Line on Aesthetics: If you value a natural, cohesive look, treated lumber is the way to go. It will ensure your deck frame blends seamlessly with your deck boards and the style of your home. Wood offers warmth and charm that metal has a hard time matching. Steel frames look modern and can be made to look neat, but they might clash with the welcoming look of a family deck in a traditional backyard. Most homeowners around the Denver suburbs choose wood for that very reason – it just looks right and feels like home.

Ease of Installation and Customization

From a homeowner’s perspective, you might not be the one physically building the deck, but ease of installation can still affect you. It influences how quickly the deck goes up, how complex changes might be, and the overall project experience. It can also influence labor costs. Here’s how treated lumber and steel stack up on installation and flexibility:

  • Building with Treated Lumber: Just about every deck contractor and carpenter in Colorado has extensive experience building with wood. It’s been the standard for deck framing for decades. What does that mean for you? It means if you call up CA Carpentry or another reputable builder in Aurora or Lone Tree, they can probably design and build a wood-framed deck with their eyes closed (not literally, of course, but it’s second nature to them!). Wood framing can be cut to size on-site easily, adjusted if needed, and is generally forgiving. Carpenters use common tools (saws, drills) and standard hardware to put it together. If during construction you decide to make a change – say, extend the deck a couple of feet or add a built-in bench support – modifying a wood frame is usually straightforward. The familiarity of wood framing often means a faster build time for most crews, too. There’s no need to wait for special parts; lumber can be sourced from local suppliers in Castle Rock or Centennial on short notice. The customization possibilities are endless with wood because you can cut and connect it in so many ways. For complex deck shapes or unique features, wood is very adaptable on the fly.
  • Building with Steel Framing: Steel deck framing is a more specialized skill. Not all deck builders offer it, so you might need to seek out a contractor who is experienced with steel. The pieces often come pre-engineered, which is great for precision, but it means everything is a bit more pre-planned. There is less room for last-minute changes without possibly ordering new parts. Installation of steel framing involves more bolts and screws (instead of nails) and sometimes special cutting tools (you can’t use the same saw blade for steel as for wood). Some steel systems are designed to assemble quickly like an “erector set,” which can be fast if the crew is trained in it. In fact, proponents say a steel frame can go together faster because the joists and beams are consistently straight and have preset attachment points​. However, if the crew is not familiar, there can be a learning curve. Also, Colorado’s terrain isn’t always flat – if your backyard in Highlands Ranch has a slope and needs custom post heights or angled corners, the flexibility of wood to be trimmed on-site can be a big advantage. With steel, every cut must be precise and any mistake could be costly. For customization, steel framing works great for standard shapes and can allow longer spans, but for truly creative, quirky designs (imagine curving edges or odd angles), wood often adapts more easily.
  • Labor and Availability: Because wood framing is so common, finding a qualified builder in our area (Castle Rock and beyond) to do a wood deck is simple. CA Carpentry’s team, for example, has decades of combined experience in wood deck construction. Steel-framed decks are a newer trend – only a few contractors in Colorado specialize in them. So, your choice of builder might be limited if you insist on steel, and they might charge a premium for that expertise. With wood, almost any good carpenter can build a solid deck frame, which can keep labor costs competitive. Plus, if you’re ever considering a partial DIY approach or future expansion, working with wood is much easier for the average homeowner or handyman than working with steel components.

Bottom Line on Installation: Treated lumber wins for ease and flexibility in most cases. It’s the “universal language” of deck builders – every crew knows how to work with it, adjust it, and get great results. This means a smoother process for you, and often a quicker turnaround from breaking ground to enjoying your deck. Steel framing can be efficient with the right team, but it’s not as universally handy. If you want a hassle-free build and the ability to customize readily, a wood-framed deck is the friendlier option.

Maintenance and Care for the Long Haul

No one wants a deck that’s a headache to maintain. The good news is that much of the maintenance of a deck is actually about the decking boards and the finish (staining, sealing, cleaning, etc.), not the frame. Still, the frame material can influence what kind of care is needed over the years:

  • Maintaining a Treated Lumber Frame: Wood frames are largely out of sight, out of mind for homeowners day-to-day. However, to get the most life from your treated lumber deck frame in Colorado, a few simple steps help:
    • Sealing and Protection: Any time the frame is exposed (like during initial construction or if you ever replace deck boards), it’s wise to apply a wood sealer or at least ensure the wood was properly kiln-dried and sealed after treatment. CA Carpentry often uses joist tape on the tops of joists to prevent water penetration into screw holes, which greatly extends the life of the wood. These tapes and flashings keep moisture off the wood frame, preventing rot in critical areas.
    • Inspections: Every few years, it’s good to peek under the deck and check the frame. In places like Littleton or Centennial, where leaves or snow might accumulate, you want to make sure no debris is constantly sitting against the wood. Simply clearing out piled leaves and ensuring water can drain will help the wood last longer. Look for any signs of cracking or warping. Some surface cracks in beams are normal as wood ages and dries, but if anything looks concerning, you can have a pro assess it. The nice thing about wood is that if one joist or one post has an issue, it’s usually quite feasible to reinforce or replace that piece without tearing out the whole deck.
    • Restaining (If Exposed): If any parts of the frame are visible and stained to match the deck, you’ll want to re-stain those when you do the decking so everything stays protected and looking uniform. Generally, the frame is under the decking boards and not exposed to UV, so it doesn’t need re-staining like the top surface does.
  • Overall, a treated lumber frame doesn’t demand much from you. Keep it dry, inspect occasionally, and it will quietly do its job for many years.
  • Maintaining a Steel Frame: Steel frames are often advertised as “low-maintenance” and that is true to an extent. You won’t need to paint or seal them yearly like you might with a wooden deck surface. However, low maintenance is not no maintenance. With steel, the key is protecting it from corrosion:
    • Coatings: The steel comes galvanized or powder-coated to resist rust. If you (or your builder) ever drills new holes or cuts a steel piece (for example, trimming a beam to length), the exposed metal should be touched up with rust-inhibiting paint. Keeping the protective coating intact is crucial. If you notice any scratches or chips in the frame’s paint, it’s wise to seal them up sooner rather than later.
    • Inspections: It’s actually a good idea to inspect a steel frame periodically as well. Check for any rust spots, especially around connections and fasteners. Steel can also make creaking noises with temperature changes (metal expanding and contracting), though this isn’t a structural problem, it might catch your attention. Tightening any loose bolts can be part of maintenance.
    • Fastener Care: With steel, all the bolts and screws are metal too. In the dry air of Colorado, you might not worry about them, but if any part was not galvanized, it could rust and stain or weaken. So ensuring all hardware is weather-resistant is important from the start. This is something CA Carpentry and quality builders handle during construction, of course.

In terms of lifetime, a well-kept steel frame will likely outlast a well-kept wood frame. But practically, a wood frame can last a very long time – long enough that you might replace the deck for style or move houses before the frame ever fails. The maintenance difference is not huge; both materials benefit from a watchful eye and a little care. Treated wood might need a bit more preventative care (like sealing tape and occasional resealing), whereas steel needs vigilance against rust.

Bottom Line on Maintenance: If you’re looking for the easier upkeep, you’re not going to be overwhelmed by either choice. Treated lumber decks in Colorado need surprisingly little attention on the framing if built correctly – just keep them dry and inspect now and then. Steel frames are similarly hands-off, aside from guarding against rust. Neither one is as much work as, say, re-staining your deck surface or shoveling snow off in winter. So maintenance is not a deal-breaker for wood at all. With modern treatments and a good builder’s techniques, a wood frame is relatively worry-free for homeowners.

Why Treated Lumber is Great for Colorado Decks

We’ve touched on many points, but let’s emphasize why, specifically for Colorado’s climate and our local communities, treated lumber framing makes a lot of sense:

  • Handles Temperature Swings: We know how wild Colorado temperature swings can be – a morning frost can turn into a 60°F afternoon, or a hot day can drop to a cool night. Wood has natural insulating properties and changes temperature more slowly than steel. This means it’s less prone to condensation and doesn’t rapidly expand or contract with sudden temperature shifts. In places like Castle Rock or Franktown where you can get a surprise overnight freeze, a wood frame takes it in stride without the homeowner ever noticing a thing.
  • Proven in Our Weather: Treated lumber has been used in Colorado for decades to build decks, patios, and even home foundations. It’s a proven material for our high altitude UV exposure and dry air. Colorado’s climate is actually gentler to wood frames than a humid Southern state – we don’t have year-round moisture that causes rot easily. The key challenge here is the sun and dryness, which is solved by using quality lumber and keeping it sealed. CA Carpentry often uses premium grade, kiln-dried lumber that’s less prone to warping. We know what works here. Steel is newer on the scene, and while it’s performing well, it doesn’t have the same long track record in thousands of Colorado decks. Treated lumber is a trustworthy choice that’s not going to surprise you.
  • Resists Weather with Treatment: Pressure-treated wood is named that for a reason – it’s treated to resist weather. The chemical preservatives guard against moisture intrusion and fungal decay. So when we do get those summer thunderstorms in Aurora or a foot of heavy spring snow in Highlands Ranch, your wood frame is prepared. As the snow melts or rain dries up (quickly, in our state!), the treated lumber is left none the worse for wear, especially if it’s built with good drainage and flashing. You can enhance this by adding simple deck flashing and drainage solutions, which CA Carpentry includes in our deck projects to protect the frame.
  • Comfort in Heat and Cold: Here’s a small but nice perk – if you ever go underneath your deck (for storage or when gardening around it), a wood frame is nicer to the touch on a very hot or very cold day. Steel can get extremely hot under the sun and awfully cold in winter. Wood won’t burn your hand or freeze your fingers if you touch it while fiddling with something under the deck. It’s a minor everyday comfort, but in Colorado’s sunny summers, anything metal can become a skillet in the sun!
  • Local Supply and Sustainability: Colorado has access to plenty of lumber, and using wood is also an eco-friendly choice when done right. Wood is a renewable resource, and many suppliers in the region source from sustainable forestry operations. Treated wood does use chemicals, but those treatments have become much safer for the environment over the years. There’s also the factor of supporting local lumber yards and the timber industry, which has been part of Colorado’s economy for a long time. Steel, while recyclable, is produced far away and has a higher carbon footprint in manufacturing. If building green is a consideration for you in Centennial or Littleton, a wood deck frame is aligned with that ethos, especially if the wood comes from regional sources.

In summary, Colorado’s climate was practically made for well-built wood decks. They handle the sun, the dryness, and the occasional moisture with grace. When you choose a treated lumber frame, you’re choosing a material that “grew up” in nature and belongs in the great outdoors of Colorado. It’s a choice that just makes sense for our environment and lifestyle.

CA Carpentry’s Custom Deck Expertise in Your Neighborhood

When investing in a new deck, the builder you choose is just as important as the materials. At CA Carpentry, we’ve been building custom decks since 1995, right here in Colorado. We’re based in Castle Rock and have crafted beautiful outdoor spaces all over the region – from Aurora’s modern suburbs to the foothills near Franktown. Our experience has proven to us that high-quality treated lumber framing is an excellent choice for Colorado decks. It provides the longevity, strength, and beauty our clients expect, and it keeps projects within a reasonable budget.

Some things that set CA Carpentry apart when building decks in Castle Rock, Parker, Highlands Ranch, Lone Tree, Centennial, Littleton, and surrounding areas:

  • Local Knowledge: We know the soil conditions, weather patterns, and building codes of these areas. Whether it’s ensuring a deck in Littleton can handle heavy snow or designing a deck in Aurora to catch the best sunset views, we tailor our approach to each location. Our familiarity with local permitting in Douglas and Arapahoe counties also helps your project go smoothly.
  • Quality Materials: We don’t cut corners. For wood frames, we hand-pick or specify premium treated lumber that is less likely to warp or twist. We often use kiln-dried after treatment (KDAT) lumber, which means the wood is dried to a stable moisture level after being treated – this helps prevent that “shrink and crack” issue some standard treated lumber can have. We also incorporate moisture barriers (like joist tape and flashing) in every deck to extend the life of the frame. The result is a wood structure that is built to last in the Colorado climate.
  • Expert Craftsmanship: Our team has built hundreds of decks. From ground-level patios in Centennial to two-story decks with panoramic views in Castle Rock, we bring skilled craftsmanship to each project. We understand how to design a deck frame that not only meets engineering requirements but also supports the special features you want – maybe a built-in fire pit or a pergola top. We make sure the framing is rock-solid and ready to hold all the good times you’ll have on your deck.
  • Customization and Design: Because we stick with the tried-and-true lumber framing, we have incredible flexibility in design. Your deck doesn’t have to be a simple rectangle (though it can be if you like!). We’ve created decks with sweeping curves, multiple levels, and custom insets for hot tubs or planters – wood framing makes these creative designs feasible. We love working with homeowners to personalize decks. Have a unique idea? We’ll figure out how to build it with our wood framing techniques and make it a reality.
  • Trust and Transparency: Being a local Castle Rock company, our reputation in the community is everything. We pride ourselves on honest advice. If we truly believed steel framing was a must-have for your dream deck, we’d tell you. But in most cases, and from years of seeing decks stand the test of time, we find that a well-built treated lumber frame is the smart choice for our clients. It offers the best mix of quality and value. We stand behind our work, so you can rest easy knowing your deck is built right.

By choosing CA Carpentry, you’re not just getting generic deck builders – you’re getting neighbors who care about the finished product as much as you do. We take into account things like the gorgeous view from your Highlands Ranch backyard or the way the sun hits your Parker porch in the afternoon. All those little local details inform how we design and build your deck.

Conclusion: Wood Deck Framing is a Win for Homeowners

After comparing all these factors – cost, durability, looks, installation, and upkeep – it’s clear that pressure-treated lumber framing has a lot of advantages for Colorado homeowners. Steel framing certainly has its benefits and might be the right choice for some situations, but for most folks looking to add a beautiful, reliable deck to their home in the Denver South area, treated lumber is the top choice. It’s affordable, strong enough to weather our climate, visually warm and inviting, and built by contractors who know it inside and out.

Your deck is where you’ll sip coffee on a fresh spring morning, host summer barbecues, or watch the aspens turn golden in the fall. It should be built to last and to reflect the comfort of your home. A treated lumber frame provides a sturdy foundation with a welcoming feel – truly the best of both worlds.

Ready to Build Your Dream Deck?

If you’re considering a new deck in Castle Rock, Aurora, Highlands Ranch, Parker, Lone Tree, Centennial, Littleton, or Franktown, we invite you to reach out to the experts at CA Carpentry. We specialize in custom decks tailored to your needs and Colorado lifestyle. Contact us today for a free custom deck consultation and let’s talk about your vision. We’ll help you design the perfect outdoor space and choose the right materials – whether it’s a classic wood deck or any other style that suits you. With CA Carpentry’s experience and personal touch, you’ll be enjoying your new deck in no time. Don’t wait – let’s get started on creating your very own outdoor oasis!

(CA Carpentry is proud to be your local Castle Rock deck builder, serving the community since 1995. We love helping our neighbors create amazing decks and outdoor living spaces. Give us a call or schedule your consultation, and take the first step toward the deck you’ve been dreaming of.)