Two Different Worlds: Acoustics and Insulation

Vince Bailey / May 2023

Exceptions—always exceptions. It seems that whenever we make any general statement assuming some air of authority, we leave ourselves wide open for the usual pokes from readers seated in the heckler’s section (“Yeah, but what about …?). It comes with the territory. Sometimes I think it might be best to preface any blanket statement with a disclaimer: “Of course there are exceptions, but …” and so on, but that would be stating the obvious.

Such is the case with our contention that cross-scope broadening is a positive move for (OK, most) wall/ceiling contractors. There are just so many good reasons for such expansion, that we make that case with little reservation. And it does make good sense for us to do so for a number of reasons. Scheduling coordination, scope overlap, cost-cutting, similar work force skills, possible sharing of equipment and lessening of inter-trade frictions are just a few payoffs of a multi-scope approach for subcontractors. Then there’s the indisputable fact that general contractors encourage the submission of combination proposals. They obviously prefer the practice of dealing with a single entity during the performance of a project, rather than playing referee to a flock of specialty contractors who often create gaps between their stated scopes. And then there’s the added value that bundling can present to a GC by overlapping certain aspects of the work.

Still, we concede that, yes, there are exceptions, and there’s one worth exploring in some detail. We cite the curious instance between two seemingly compatible trades with apparent complementary aspects that rarely, if ever, result in an occupational joining—the case of acoustics and its cousin trade, insulation. I say cousin contractors because they do share some irrefutable commonality that might ostensibly make them candidates for merging. After all, both trades deal significantly with a sound factor, so we have overlap of scope. Then too, both trades share a common scheduling window (framing/drywall phase). Moreover, there is an opportunity to share some equipment (small tools, scaffold, trucks). And of course, there’s the single-contractor-for-multiple-scopes aspect that piques the interest of the GCs.

Why then, you might wonder, are there virtually no subcontractors to be found who offer an integration of the multiple scopes defined as acoustics and insulation? To even approach a possible answer, we need to clearly identify the multiple scopes of work performed by a typical acoustical subcontractor versus those of an insulation subcontractor.

The Acoustical Contractor
Very basically, an acoustical contractor will typically provide and install acoustical tile ceilings, specialty ceilings and acoustical wall panels. Again, fundamentally, an insulation contractor will provide and install acoustical and thermal insulation, often in conjunction with providing certain sealant assemblies, including acoustical caulk. But basics don’t tell the whole story. We begin to grasp the differences between the subcontractors’ work as we drill down into the details behind the general descriptions—differences that might cause us to question the notion of commonality between the two subs’ contributions to a project.

In the case of a typical acoustics contractor, we focus on his main product: acoustical tile ceilings—on its face, a simple assembly consisting of a suspended metal grid supporting a matrix of sound deadening panels. Sounds like a simple scope of work with few barriers to entry. But the façade of simplicity is shattered by the various optional components, the number of which is stunning in volume.

Says Kim DeBacco, estimator/PM for T-P Acoustics, “The number of different tiles we deal with coming from a single supplier is hard to nail down.”

Indeed, one grid ceiling manufacturer boasts no fewer than 138 mineral fiber ceiling tile types (88 commercial tiles and 50 types strictly intended for residential application). These units vary in terms of dimension (2-by-2 or 2-by-4), configuration (square-edge, beveled tegular and scored) and by performance specification (sound absorption, sound transmission and light reflectance). In addition to mineral fiber panels, there are various other materials that fit into a suspended grid system, including wood, metal, mesh, fabric and excelsior. That’s just tile. Then there are two basic grid sizes (widths): 15/16” and 9/16” plus several specialty grid components that allow the creation of different shaped “clouds.” Clearly, simple reference to “grid ceilings” belies the vast combinations of possible options for numerous assemblies, and that’s without even getting into color. A full service acoustical contractor also provides his client with specialty assemblies that combine acoustics with aesthetics—stretch fabric, linear metal, hanging baffles and wood ceilings, plus a variety of acoustical wall panels, all of different configurations, fabric wraps and varied installation processes. Evidently, the depth of product options alone renders the field of acoustics anything but simple.

The Insulation Contractor
Similarly, an insulation contractor offers provision and installation of a number of assemblies, some of which are quite surprising in their diversity. Focusing on the insulation contractor’s mainstay, batt (or, blanket) insulation, we are staggered once again by the variety of possible components within that division alone.

To begin with, there are two basic types of batts that function with different purposes: those that regulate heat transference and those that regulate sound transference—i.e., thermal and acoustical insulation. Batts generally come in two different widths, 16 and 24 inches, to accommodate the spacing of framing cavities between field studs. Their effectiveness, however, is determined by type, differing thicknesses and density. Both thermal and acoustical insulation effectiveness can be rated by R-value, which stands for resistance, that is, resistance to heat or sound passing through. The higher the R-value, the greater the resistance and effectiveness of the batt for regulating transference. As stated, R-value is derived from type, density and thickness of the batt.

Regarding type and density, batts are usually comprised of one of three materials—fiberglass, mineral wool and cellulose (recycled paper), in order of common usage, but reverse ordered with regard to density. Thickness of the batt is obviously determined by the depth of the cavity being filled.

Batt insulation is further diversified by its application. Where acoustical insulation is commonly unfaced, thermal batt insulation typically applies with an adhered Kraft (asphalt-impregnated) paper or foil scrim (for flame-proof applications), providing an integrated vapor barrier to the assembly. And where acoustic insulation is typically applied to interior space separation walls and floor/ceiling assemblies, thermal insulation is used on exterior walls and roof cavities.

In addition to batt insulation, a full service insulation contractor will also provide and install rigid board insulation (Styrofoam or compressed fiberglass), blow-in attic insulation (fiberglass or cellulose), or urethane spray-foam applications (open or closed cell). Deviating slightly from the typical cavity fillers, many commercial insulation contractors are becoming involved with the application of joint sealants. These applications entail sound caulking, expansion joints and fire caulking—the latter in the form of slab-edge firestops, wall penetration treatment and head-of-wall detail.

A Closer Look
Certainly our descriptions of the work of these commercial contractors fall short of completely defining them, but we learn as we drill into the specific scopes of typical acoustic and insulation service providers the differing intricacies involved with each division. We might now begin to recognize a developing divergence between the two—that our original assessment that these are complementary businesses, ripe for merging, might be ill-conceived.

There are a number of approaches to analyzing the differences between the two types of firms, but specialization emerges as the most dominant factor. We have focused on the nature and specialization of materials used for the products of each contractor. And while this serves as a basis for citing a strong divergence between trades, it really only begins to tell the story.

The unique products offered by each type of firm require unique skill sets from estimating, through project management, down to the field installers. Take some application that seemed simple on its face—ACT (acoustical tile ceilings), for example. Just to begin on an estimate for this scope, the quotesmith must be knowledgeable with the numerous components of a grid ceiling and be working with an estimating program that includes all the various tile types supplied by a number of different manufacturers (in the several hundreds) in its database. Project managers must know how to order the materials, and, perhaps most importantly, field installers must know how to best assemble the components for an acceptable finished product at a rate that renders the job profitable.

Here we must take a closer look at labor, because it is a sticking point for any notion about expanding scope (or expanding at all). As we stated, specialized work calls for specialized skill sets, and with the labor shortage that the entire industry is now experiencing, most outfits are hard pressed to hire more bodies, much less recruit skilled installers. This applies across the board to all of the sub-scopes that we’ve cited—from grid ceiling installers to insulators.

As Roger Harris, business development manager for Rite-Way Thermal, put it: “We have our hands tied by the labor shortage. We could do twice the volume we are doing right now if we just had the people.” But it is more than just bodies that are needed. The assemblies described above require installers who possess specialized skills—talents that are gained through experience and training. In fact, certain scopes require certification, as in the case of fire caulk installers. Given these circumstances, it’s no wonder that most specialty subcontractors are content with maintaining a comfortable volume, working with what they’ve got—expansion or broadening of scope be damned.

Can It Work?
And so we begin to question our original contention that the two scopes of work are complementary and suitable candidates for merging. Our strongest argument began with an overlap of scope—that is, both acoustic and insulation contractors deal with sound issues. But on closer examination, we find their approach differs with dissimilar objectives. Where insulation contractors concern themselves with sound transmission (measured by sound transmission class, or STC), acoustical contractors focus on sound absorption (measured by noise reduction coefficient, or NRC).

Moreover, our notion that the two scopes share a scheduling window appears to be a stretch, as most of an insulator’s work is performed during the framing phase, where acoustics come into play after finished drywall and paint. This underscores another basic difference between the two scopes: insulation, which is concealed from the public, is solely concerned with performance, where acoustical assemblies are visible, and so they combine performance with aesthetics.

We also fell prey to the myth that the labor for each of these scopes is similarly performed by unskilled workers. Our previous in-depth look at the knowledge and skill required to install the products at issue dispels that misconception quite handily.

And so we’ve made a case for the naysayers who like to focus on exceptions. While we still hold that most merging or absorption of scopes is a healthy practice, trying to marry acoustics with insulation will evidently stump any matchmaker. However, their scopes can be (and often are) combined under the umbrella of a commercial drywall contractor as second tier subs. In these instances, all the scopes we have discussed can live together in harmony, and we can safely call acoustical and insulation contractors cousins. Of course, there are exceptions.
Vince Bailey, an estimator/project manager in the Phoenix area, also writes the Estimator’s Edge column for this magazine.

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