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Marine & Boat

Lewmar and Bomar Acrylic Portlights and Hatch Lenses

The two portlight and hatch brands on most production sailboats and cruisers, reviewed as a glazing product. Lewmar (Havant, England, owned by Lippert since 2019) publishes lens thickness, CE area ratings, and a code-based spares program; Bomar (Pompanette, Charlestown, New Hampshire) is a US foundry-to-finish builder whose lens material varies by series. Both craze in the sun eventually; the difference is how easy the fix is.

By , Founder & Editor · Updated · How we research

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$39–$394 per replacement lens; $110–$650 per complete portlight
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Key facts

  • Lewmar, based in Havant, England and owned by Lippert since August 2019, makes acrylic hatches and portlights for boats.
  • Bomar, a division of Pompanette in Charlestown, New Hampshire, makes hatches and portlights and uses polycarbonate lenses on its 100 Series cast hatches.
  • Lewmar stamps a lens code into hatches and portlights made after July 2007 and sells matching lens kits from $132.
  • Lewmar warrants its products for three years, excluding UV degradation; Bomar warrants for one year against manufacturing defects.
  • AcrylicWindow.com rates Lewmar and Bomar lenses and portlights 4.0 out of 5.

Pros

  • Lewmar publishes acrylic thickness per hatch line (8, 10, or 12 mm), CE area ratings, and a lens-code identifier that turns the stamp on your old acrylic into an exact spare
  • Complete Bomar fixed portlights from about $110 surplus, and Lewmar Standard Portlight lenses from $39
  • Lewmar replacement hatch lenses arrive with seal pre-mounted and new handles, so a re-lens is a slide-apart job rather than a sealant scrape
  • Three-year Lewmar warranty on the product; both brands still make parts for hatches sold decades ago
  • Bomar builds frames, castings, and anodizing in-house in New Hampshire, and still exhibits at the major trade shows in 2026

Cons

  • UV crazing is the known failure on both brands; owners report Lewmar lenses going cloudy in under three years on a sunny mooring, and Lewmar's warranty excludes UV degradation
  • Bomar's product pages call the same lens 'acrylic' and 'polycarbonate Lexan acrylic'; the parts list shows 100 Series cast hatches actually use polycarbonate
  • Bomar warranty is one year, replacement-lens prices are not published, and one owner was told his model's lid was not sold separately
  • Lewmar lens kits fit MK2 hatches only, and units before July 2007 have no code and need manual identification
  • Neither maker says whether the acrylic is cast or extruded, or names the sheet brand

Specifications

MakerLewmar Ltd, Havant, Hampshire, UK (Lippert Components since Aug 2019; US office Guilford, CT); Bomar, a division of Pompanette LLC, Charlestown, NH
MaterialAcrylic on all Lewmar lines and most Bomar series; polycarbonate (Lexan) on Bomar 100 Series cast hatches; cast vs extruded not stated by either
ThicknessLewmar Low Profile 8 mm (size 60: 10 mm), Ocean 10–12 mm, Medium Profile 12 mm, Standard Portlight 8 mm; Bomar A&P lenses 1/4 or 3/8 in, 9 in round portlight lens 3/8 in
TintsLewmar: grey, green, clear (portlights add smoke); Bomar: smoke standard, white optional, frosted and clear on some portlights
StandardsLewmar: ISO 12216 Area 1 or 2 per model, CE marked; Bomar: CE approval offered as an option, no area ratings published
Lens IDLewmar code stamped in the acrylic on hatches and portlights made after July 2007; Bomar by series and part number
WarrantyLewmar three years, one year on weather seals, UV degradation excluded; Bomar one year against manufacturing defects
PriceLewmar Standard Portlight lens $39–$94; Low Profile lens kit $132–$256; Medium Profile lens kit $228–$394; Bomar fixed portlights $110–$237 surplus, opening SS Flagship $649; Lewmar Medium Profile hatches $657–$2,302
SealantDOWSIL 795 structural silicone, cited by owners and used in factory re-lens work; spacers to hold bond thickness
SupportLewmar ustechsupport@lewmar.com, +1 203 458 6200; Bomar/Pompanette 603-826-5791

Our Verdict

For a crazed or cracked lens on a boat that came with Lewmar, buy the Lewmar kit: the code makes it unambiguous, the seal and handles come attached, and the thickness matches what the CE rating was earned with. For Bomar, call Pompanette with your series number before assuming a lens is available, and expect a one-year warranty. If the frame is corroded or the sealant job scares you, a complete surplus portlight from Great Lakes Skipper is often cheaper than a rebuild. Either way, keep ammonia and petroleum cleaners off the lens and put covers on the hatches, because the sun is what kills them.

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Overview

If you own a fiberglass sailboat or cruiser built in the last forty years, the deck hatches and portlights probably say Lewmar or Bomar. Both companies sell complete units, and both sell the piece that actually wears out: the acrylic lens. That is why they earn a place on a site about acrylic windows. A hatch frame will outlive the boat. The lens will craze, the seal will harden, and at some point you will be searching for a part number with a caliper in your other hand.

This review treats the two brands as a glazing product. What is the lens made of, how thick is it, what does it cost to replace, what does the warranty actually cover, and how do owners get on with it? The answers differ more than the shared reputation suggests. Lewmar publishes specifications and runs a spares program built around a code stamped in the acrylic. Bomar builds a solid frame in a New Hampshire foundry but leaves you to phone for lens prices and, on some series, to work out whether the lens is acrylic at all.

The two companies

Lewmar was founded in 1946 and is based in Havant, Hampshire, England, with a US office in Guilford, Connecticut. Lippert Components, the Indiana RV and marine supplier, bought Lewmar Marine in August 2019 for roughly $40 million, and Lewmar hatches and portlights now sell direct on lippert.com alongside the dealer network. The catalog families are Low Profile, Medium Profile, and Ocean hatches, plus Standard and Atlantic portlights, with older lines (SuperHatch, Rollstop, Trimline, Coastline, Concept) still supported for spares.

Bomar is "a division of Pompanette, LLC," at 73 Southwest Street, Charlestown, New Hampshire. Pompanette dates its marine manufacturing back nearly fifty years and Bomar's hatch and port business nearly thirty. It is vertically integrated in a way few marine hardware companies still are, with its own aluminum foundry, CNC machining, and anodizing, and it states that all products are made in the USA. Rumors of Bomar's demise circulate on owner forums; we found none supported. The company exhibited at Pacific Marine Expo in Seattle in November 2025, is registered for IBEX in Tampa in October 2026, and announced a showroom reopening in June 2026. The phone number on bomarusa.com in 2026 is the same one a forum poster quoted in 2002.

Lens material and thickness

Lewmar's catalog prints the acrylic thickness for every hatch size, which is more than most makers manage. Low Profile hatches carry an 8 mm (5/16 inch) lens in sizes 00 through 54, and 10 mm in size 60. Ocean hatches use 10 mm in sizes 10 to 40 and 12 mm from size 44 up. Medium Profile hatches use 12 mm (1/2 inch) throughout, and Fisheries Supply describes that lens as "shock resistant" and tested to 2 psi for CE Area 2a. The Standard opening portlight carries an 8 mm lens. Tints are grey and green on hatches, with clear, green, and smoke on portlights.

What Lewmar does not say is whether the sheet is cast or extruded, or who makes it. The product pages offer "strong," "durable," and "tough" acrylic and nothing more. A hatch shop's claim that Lewmar uses cast ACRYLITE is plausible and consistent with a 12 mm lid, but it is a third-party claim we could not verify against Lewmar's own material. Our cast vs extruded explainer covers why it matters: cast resists crazing and solvents better, which is exactly the failure these lenses suffer.

Bomar's material story needs a caveat every time it is told. The 2000 Series, A&P Series, and 900 Series pages each describe the lens as "heavy duty, smoked acrylic standard" and, on the same page, as "smoked polycarbonate Lexan acrylic lenses," which is not a material. Pompanette's replacement-lens catalog resolves it by part: the 100 Series cast hatches (130 square, 139 rectangle) take Lexan polycarbonate lenses; the 190 Series cast hatches, the 900 Series molded hatches, and the A&P Series take acrylic, with A&P lenses offered in 1/4 or 3/8 inch, smoke or white. Bomar portlight lenses sold at retail, such as the 9-inch round at 3/8 inch, are acrylic. Bomar publishes no lens thickness by portlight series. Polycarbonate scratches more easily and yellows faster than acrylic without a UV cap, so on a 100 Series hatch, cleaners and cover habits matter even more.

On standards, Lewmar's Hatch and Portlight Fitting Guide states that all product complies with ISO 12216 and gives an area rating per model: Medium and Low Profile hatches and opening Standard portlights are Area 2 (deck, coachroof, cockpit, transom); fixed Standard portlights in sizes 0 to 2 and fixed Atlantic portlights are Area 1 (hull sides above the waterline). The guide is an older document that cites the superseded Recreational Craft Directive, so treat the per-size ratings as historical and confirm with Lewmar for a new install. Bomar lists "CE Approvals" only as an option on its hatch series and publishes no area ratings. Neither brand mentions ABYC H-3 anywhere we could find.

Replacement lenses

Lewmar has the better program, and it starts with a code. Every hatch, portlight, and fixed light made after July 2007 carries a lens code stamped into the acrylic: on hatches between the right-hand handle and the edge of the lens, on portlights under the Lewmar branding. Lewmar's identifier page turns that code into a part number. Anything older needs manual identification from the family and size, and there is one trap: the current replacement kits are built for Mk2 friction-lever hatches only. A Mk1 shows a visible roll pin near the hinge.

The kit itself is the good news. A Medium Profile or Low Profile replacement arrives as a lens with the seal pre-mounted and new handles and friction-lever cap fitted; you slide the two halves of the frame apart, swap the lens, and slide them back. Hinges are not included. Defender's 2025 listings put the Medium Profile kit at $228 to $394 across sizes 30 to 70, the Low Profile kit at $132 to $256, and the bare Standard Portlight lens, which fits the 1997-and-earlier ports, at $39 to $94 in clear, green, or smoke. UK chandlers sell the same kits on request.

Bomar lists 18 deck-hatch lenses and 11 portlight lenses on Pompanette's site by series and part number, from Gray Series and Molded Flagship portlight lenses to A&P hatch lenses in two thicknesses. Prices show as zero or not at all, and lead time is quoted as one to two weeks; you call for a quote. Availability is model-dependent. A Rinker 350 owner was told in 2021 that his hatch lids were not sold separately and that he would have to buy whole hatches at $745 each; he ended up having three lenses cut from 6 mm cast charcoal-grey acrylic for about $150 and bedding them in DOWSIL 795. Retail surplus fills some gaps: Great Lakes Skipper sells a 9-inch round Bomar portlight lens in 3/8-inch smoke acrylic for $48 on sale, with the warning that surplus stock may carry storage scuffs.

Complete portlights and hatches

When the frame is corroded or you do not want to scrape sealant, a complete unit can be the cheaper path, especially for Bomar. Great Lakes Skipper, which sells boat-builder overstock, listed 42 Bomar portlights in September 2026: a 6.5-by-16.75-inch fixed clear-lens port at $110, a 4-by-14.5-inch Molded Flagship at $137, several stainless fixed ports around $176 to $216, and an 18-by-8.5-inch smoke fixed port at $237. Those are sale prices on surplus and they move. A new SS Flagship elliptical opening portlight with screen and trim ring lists at $793 and sells for $649 at WMJ Marine.

Lewmar complete units cost more because they are current production sold through dealers. Fisheries Supply prices Medium Profile hatches from $657 for a size 30 to $1,131 for a size 70 and $2,302 for a size 77. A Standard opening portlight in size 1 runs about £188 in the UK; Lippert sells it direct in the US with a three-year warranty and a stated hull-thickness range of 1/4 to 1-3/8 inches. West Marine's Ocean hatches run roughly $445 to $1,210.

Warranty

Lewmar's printed terms warrant its products "for a period of three years from the date of purchase by the end user" in normal private pleasure use, with repair or replacement at Lewmar's option. The exceptions matter for glazing. Cover drops to one year for hatch and portlight weather seals, and for products in commercial, charter, or Grand Prix racing use, and the warranty excludes "corrosion, ultra violet degradation or wear and tear." Since UV is what crazes a lens, a cloudy lid at year two is not a warranty conversation, whatever an owner on a forum once told you.

Bomar's line is one sentence: "All Bomar hatches are backed by our 1 year warranty against any manufacturing defects." Same exclusions in practice, shorter term.

Crazing and what owners report

The failure mode is consistent across two decades of forum threads. A Catalina 36 owner reported in 2005 that the Lewmar hatches on his 2000 boat "went south after only 2 1/2 years" while the 1990 Catalina 30's had lasted a decade; a Lewmar representative in the same thread said "UV is definitely the culprit." Another Catalina 36 owner in 2012 was quoted $456 plus freight to re-lens a hatch in 3/8-inch smoked acrylic, and a third put it bluntly: "Bomar hatch is fine, but the Lewmar hatches all craze." Bomar owners have their own threads, with a C-Dory owner in 2020 describing a hatch lens "all cracked" and a new Bomar hatch at $745, and Rinker owners with all three hatches crazed.

Chemistry does the rest. Owners repeatedly warn against glass cleaner: "NEVER use glass cleaner. This WILL cause the material to fog and craze. Use dish soap and water ONLY." Ammonia and petroleum distillates are the specific enemies; our scratch repair guide covers polishing fine haze, but crazing goes through the surface and does not polish out. Hatch covers are the prevention owners recommend most.

Leaks are the other complaint, more often on Lewmar portlights, and the culprit is usually the seal or the joint in the outer frame rather than the lens. Seal replacement is a two-hour job and, on the Bomar side, owners buy generic closed-cell gasket rather than Pompanette's, with reports of two seasons dry.

Re-lensing yourself

On a Mk2 Lewmar, the kit does the work. On a Bomar or an older Lewmar, the job is a bedding job, and the forum consensus on materials is unusually firm. The sealant is DOWSIL 795 structural silicone, "the same caulk used to hold windows in place on high rise buildings," and Lewmar itself sets the lens in it. Set the lens on 1/16-inch foam spacers so the silicone keeps a bond thickness, clean the frame and the lens edge with isopropyl alcohol rather than acetone (one owner's acetone-cleaned frame refused to bond), and keep everything above 50°F through the cure. Drill acrylic from both faces, as Lewmar's fitting guide says, or the exit side breaks out.

Owners who cut their own lenses at a plastics shop paid about $15 for a 13-inch square Bomar lens and $40 for a 21-inch Lewmar in 2012, and $150 for three 6 mm cast lenses in 2023. Specify cast sheet. Some owners have gone to 1/2-inch Lexan believing it will not craze; it will, and it scratches faster, so stay with acrylic unless the original was polycarbonate. Our boat window roundup covers the sheet itself.

Alternatives

Select Plastics, also trading as HatchMasters, in Norwalk, Connecticut, is the re-lens shop owners recommend most, at roughly $456 to $545 per hatch with new hinges in 2012 pricing. Its site showed a "temporarily closed" notice dated July 2026, so confirm it is taking work before shipping a frame. Beckson Newport plastic opening ports start around $250 and suit a hull up to 3/4 inch thick. New Found Metals in Port Townsend, Washington, builds bronze and stainless portlights in 8 or 10 mm tempered glass for owners who have had enough of plastic. And Boat Outfitters will cut a flat acrylic lens to your dimensions if the local shop cannot.

Who should buy it

A boat owner with a crazed or cracked lens in an otherwise sound frame. If it is a post-2007 Lewmar, read the code, order the kit, and enjoy the easiest re-lens in the business. If it is a Bomar, call Pompanette with the series and part number before assuming a lens exists, and price a surplus complete unit from Great Lakes Skipper against it. If it is anything older or unmarked, budget a plastics-shop lens, a tube of DOWSIL 795, and a Saturday. In every case, buy hatch covers, and throw out the Windex.

Sources

Frequently asked questions

How much does a replacement Lewmar hatch lens cost?

Defender listed Lewmar Medium Profile replacement lens kits, with seal and handles attached, at $228 to $394 depending on size, and Low Profile kits at $132 to $256, in its 2025 listings. A bare Standard Portlight lens for the pre-1998 ports runs $39 to $94 in clear, green, or smoke. Complete Medium Profile hatches at Fisheries Supply run $657 for a size 30 to $2,302 for a size 77, so the lens kit is roughly a third of a new hatch.

How do I find the right replacement lens for a Lewmar hatch?

Look for a code stamped into the acrylic itself: on hatches it sits between the right-hand handle and the edge of the lens, on portlights and fixed lights it is under the Lewmar branding. Lewmar's online identifier accepts codes from products made after July 2007 and returns the part number. Older hatches need manual identification from the family, size, and the Mk1 or Mk2 hinge, and the replacement kits are made for Mk2 friction-lever hatches only. Email Lewmar tech support with photos for anything unmarked.

Are Bomar hatch lenses acrylic or polycarbonate?

It depends on the series, and Pompanette's own pages muddy it by describing lenses as both 'smoked acrylic' and 'smoked polycarbonate Lexan acrylic.' The replacement-parts catalog is clearer: 100 Series cast hatches use Lexan polycarbonate lenses, while the 190 Series cast hatches, the 900 Series molded hatches, and the A&P Series use acrylic in 1/4 or 3/8 inch. Portlight lenses sold at retail are described as acrylic. Confirm the material when you order, because the two need different cleaners and sealants.

Why do Lewmar and Bomar hatch lenses craze?

Ultraviolet light, thermal cycling, and chemical attack. A Lewmar representative told a Catalina owner in 2005 that 'UV is definitely the culprit,' and that boat's hatches had gone cloudy in two and a half years. Ammonia glass cleaners and petroleum distillates accelerate it, so wash with dish soap and water only. Lewmar's three-year warranty excludes ultraviolet degradation, so crazing is generally not a warranty claim. Hatch covers on a sunny mooring are the cheapest prevention there is.

Can I replace a Lewmar or Bomar hatch lens myself?

Yes, and owners do it regularly. A Lewmar Medium or Low Profile kit comes with the seal pre-mounted and new handles, and the frame halves slide apart to swap the lens. On a Bomar or an older Lewmar, you cut the old lens out, clean the frame with isopropyl alcohol, set the new lens on thin foam spacers, and bed it in DOWSIL 795 structural silicone, then leave it above 50°F through the cure. Owners who cut their own lenses from cast acrylic paid $15 to $50 per lens at a plastics shop.

What is the difference between Lewmar and Bomar warranties?

Lewmar warrants its products for three years from the end user's purchase date in normal private pleasure use, dropping to one year for hatch and portlight weather seals, commercial or charter use, and racing. Corrosion, ultraviolet degradation, and wear are excluded. Bomar states a one-year warranty against manufacturing defects on all hatches. Neither covers a lens that crazed in the sun, so treat the warranty as protection against a leak or a failed dog, not against age.

Is Bomar still in business?

Yes. Bomar operates as a division of Pompanette LLC at 73 Southwest Street in Charlestown, New Hampshire, with its own foundry, CNC, and anodizing. The company exhibited at Pacific Marine Expo in November 2025, is registered for IBEX in October 2026, and reopened its showroom in June 2026. We found no evidence of a sale or closure. Replacement lenses are listed on Pompanette's site without prices, and availability is model-dependent, so call 603-826-5791 with your series number.

What are the alternatives to Lewmar and Bomar replacement lenses?

A local plastics shop can cut a lens from cast acrylic sheet for $15 to $50 in the sizes owners report, and you bed it yourself in DOWSIL 795. Select Plastics in Norwalk, Connecticut, the re-lens shop most often recommended in owner forums, showed a temporary-closure notice on its site as of July 2026, so check before shipping a frame. For a whole new port, Beckson's Newport plastic opening ports start around $250, and New Found Metals builds bronze and stainless portlights with tempered glass if you want to leave plastic behind.

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