Installing Curved Exterior Trim

Accurate framing and full-size millwork templates guaranteed a precise fit

ur company builds custom One of our current projects is a large Preparation homes along Maine’s Mid- beachfront home with two round Precise roof framing is always impor- Ocoast. Over the last few years, towers, each with a conical roof. tant, but it’s especially crucial with a Trimming out the exterior of a tower tower, because any inconsistencies with by Chris Case can be slow and tedious, but with thor- the framing will create humps or flat ough planning, a skilled crew, and a spots in the trim. Therefore, as we set this scenic area between Searsport and good millwork shop, a job like this can the rafters, we double-checked the over- Brunswick has become popular with be manageable and — if the weather is hangs to keep the variance to within retirees and second-home buyers. good — fun. 1/8 inch (see Figure 1, next page).

MAY JLC 2005 1 Figure 1. Accurate framing is critical for a good-looking curved trim job. In this case, the rafter tails lined up to within 1/8 inch, measured from the plate. The curved plates were built up from four layers of 3/4-inch ply- wood, glued and screwed together.

We used pie-shaped pieces of 1/2-inch Soffits the rafter tail allowed us to slip it into a fir plywood for the roof sheathing and The architect’s design called for dado on the back of the curved fascia covered the whole roof with a layer of tongue-and-groove beaded fir soffits (Figure 3, page 4). At the last course, we Grace Ice & Water Shield. Roofing felt arranged in a diagonal pattern. The used a 3/8-inch-thick piece of stock doesn’t stand up for long to coastal soffits butt to a square-edged piece of held against the plumb cut on the winds, and the lengthy construction mahogany, where a decorative knee rafter tails to scribe a fair curve. on this job made the self-adhering bracket would be attached later (Fig- eaves membrane a good choice for a ure 2, next page). Templating temporary roof. As with the framing, we spent some The next step was to make 1/4-inch- We’ve found that good staging is crit- extra time laying out soffit bays so that thick plywood templates of the curved ical to making tricky work like this go they’d all be exactly the same size. fascia and the curving frieze board smoothly, so when we got to the point We marked the inside curve on the first that would circle the top of the tower of sheathing the roof, we set up pipe soffit board by holding it in place and below the soffit. Using the soffits, we scaffolding. We kept the scaffolding in scribing it with a compass. We worked scribed the 8-foot sheets in place and place until the tower’s cedar shingles our way out toward the fascia, blind then sent them to the millwork shop were installed and the trim had a nailing through the tongue with a trim that supplied the trim, Tidewater second coat of paint. nailer. Running the soffit 3/8 inch past Millwork of Woolwich, Maine.

MAY JLC 2005 2 Fitting Straight Windows Into a Curved Wall

2x12 rafter

T&G beaded 2x6 soffit installed Curved 3 knee wall in a diagonal /4" plywood pattern plates, glued and screwed together Double layer of Copper 3/8" sheathing drip edge

2x6 soffit

Curved crown 2x8 Curved joists Curved bed laminated and molding header fascia Curved laminated frieze with applied bead Curved extension Bracket (shown beyond) jamb

Fixed transom Sill extended to pilaster

5/4 mullion trim with applied bead

Window

Pilaster (shown beyond)

Sill extended to pilaster Figure 2. The home’s original design called for curved sash, but the custom Curved sill windows proved too expensive. Instead, Curved laminated trim with the walls of the tower were framed like applied bead an octagon, but with curved jamb exten- sions above and curved sills below to tran- Curved 2x6 wall with sition from flat to round. Wide pilasters 2x6 wall double layer of 3/8" sheathing at each corner of the octagon separate the

Curved 3/4" plywood plates, windows and receive decorative brackets glued and screwed together at the top.

MAY JLC 2005 3 Figure 3. To produce the curved fascia, the crew first in- stalled the T&G soffit (above), using a flexible straightedge held against the rafter tails to scribe the radius on the outer pieces. The soffit was then traced and the exact curve pro- vided to the millwork shop. The curved fascia (above right), glued up from strips of Hon- duras mahogany, was made with a 1/2-inch-deep dado to accommodate any slight irreg- ularities in the edge of the soffit. A stepladder allowed the cut man to reproduce the trim’s installed position at the saw (right).

Tidewater determined the radius After calculating the actual amounts bringing its head to a 45-degree angle from our original templates and, using of curved trim, we ordered 6 extra (the spring angle of the crown), the 1/4-inch laminations of mahogany, feet to account for waste. The shop shop avoided hogging out too much made the fascia and frieze boards to used a CNC router to cut out a tem- material at once. match. The radius of the decorative plate for the clamping station and It took the shop about a month to crown applied to the fascia was deter- then screwed L-shaped blocks to it for make the curved trim. When it arrived mined by adding its thickness to our the glue-up. Once dry, the blanks were on the job, we primed it with two coats original templates. For the frieze and cut to width and sanded. The crown, of A-100 oil-based primer by Sherwin- other components with a smaller band, and bed molding were profiled Williams (800/331-7979, www.sherwin radius than the fascia, we subtracted on a tilting-head shaper using custom- -williams.com). Our painting contrac- the width of the overhang from the ground knives. By making repeated tor had it tinted gray to better match original template. passes with the shaper while gradually the dark-green top coat.

MAY JLC 2005 4 Figure 4. The trim was initially cut at the roof’s pitch, then scribed for a closer fit with cedar shingles (top left). After instal- lation (top right), the carpenters fine-tuned the joints with a random-orbit sander (left), then primed nail and screw holes to prevent weathering (above). The painter would later fill the holes with auto-body compound.

Curved Fascia and Crown isn’t cheap (the crown was $80 per foot then worked our way around the tower. We cut the fascia and the other curv- and the curved fascia $35 per foot), so We have found that a cordless nail ing trim with a dual-bevel sliding miter we always erred on the side of caution, gun saves setup time and makes high saw equipped with an 80-tooth carbide- thinking it better to be conservative and work like this easier. But before we tipped blade. It’s not always easy getting make a recut or two than waste material. nailed anything off, we ran in a couple the correct miter and bevel settings The first piece of trim to go up was of screws. The screws allowed us to make when you’re working with curved mate- the curving fascia that butts into the adjustments if necessary and ensured rial, so when we found settings that main roof. We made an initial cut by that the trim was pulled tight to the worked, we recorded them for future approximating the roof pitch and then framing. A pair of cordless drills is a cuts. We also used the same cut man we made a more accurate cut by scrib- good idea, too, because they eliminate for the entire trimming process. As you ing the trim in place (Figure 4). We the need to constantly swap drilling and might imagine, this custom-made trim fastened the first piece of fascia and driving bits. We sanded the joints and

MAY JLC 2005 5 Figure 5. The crew positioned the crown molding so its top edge would be covered by the copper drip edge (top left). Quick- adjusting bar clamps kept the crown tight to the fascia while it was fastened (top right). To avoid gaps caused by seasonal movement, the carpenters used scarf joints. The cuts were spot-primed and the joints sealed with a healthy dose of caulking (above left), then fastened with stainless screws (above right).

spot-primed where needed as we went clamps, ran in some screws, and then area. It’s composed of three pieces: the along. Spot-priming is important be- finished it off with a cordless framing frieze, a bed molding at the top, and a cause it keeps the wood from weather- nailer. We like to use scarf joints instead small band molding near the bottom. ing, which could prevent good adhesion of butt joints at seams, because scarf The frieze covers the window’s curv- of the top coat. joints are less likely to open up with ing head jamb with a slight reveal; Next, we installed the curved crown. seasonal movement. because it has a bed molding at the top, Without the roofing or drip edge in we left a gap to save material (Figure 6, place, we positioned the crown by Installing the Frieze next page). For the frieze board, we holding it against a pair of squares simu- With the crown in place, we turned started where the tower roof ties into the lating the position of the shingles our attention to the frieze board. The main roof. As with the curved fascia, we (Figure 5). Before fastening, we pulled frieze finishes off the top of the tower made a rough approximation of the the crown tight to the fascia with bar and gives some visual interest to this angle by using the roof pitch as a guide;

MAY JLC 2005 6 Figure 6. The curved window jamb exten- sions (left) were installed slightly proud so they would disappear into the dado on the back of the curved frieze (below left). A bed molding hides the gap at the top of the frieze while the applied bead (below) adds visual interest.

then we scribed the frieze in place for a bottom of the frieze. mill shop, trimming out the towers more accurate cut. Because we had solid Before taking down the scaffold, we went smoothly. With three carpenters, framing behind the frieze, we didn’t had our painter fill all the nail holes installing the windows and exterior need screws or clamps to draw it tight; with auto-body filler and paint the trim trim took just over a week to complete. we just used the cordless framing nailer. with two coats of acrylic-latex Super- We estimated the labor for this home With the frieze circling the entire Paint from Sherwin-Williams. Then the based on labor costs for past projects top of the tower, we installed the bed roofer installed a custom copper drip and then increased the amount by 25 and band molding. The bed hides the edge fabricated by Coastal Copper and percent to account for the home’s gap at the top of the frieze. It was Slate in Rockland, Maine, to support added complexity. installed — like the crown molding — the overhanging cedar shingles and to on the fascia. Similarly, a decorative finish off the crown detail. Chris Case is a foreman with Boothbay band molding was installed near the Once we had all of the parts from the Home Builders in Boothbay, Maine.

MAY JLC 2005 7