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General Finishes Exterior 450 Water-based Top Coat Semi-Gloss, Quart
General Finishes Exterior 450 Water-based Top Coat Semi-Gloss, Quart Item #32628
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SAVE $2.50 (10%) Special Price $22.49 Quart $24.99 Quart
General Finishes Exterior 450 Water-based Top Coat Semi-Gloss, Gallon
General Finishes Exterior 450 Water-based Top Coat Semi-Gloss, Gallon Item #33028
In stock
SAVE $7 (10%) Special Price $62.99 Gallon $69.99 Gallon

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General Finishes Exterior 450 Water-based Top Coat Semi-Gloss

A tough, clear semi-gloss finish that will reduce fading and greatly lengthen the life of any exterior wood.
Item #
GRP18526
Rating:
96% of 100

Here's a tough, clear finish that will shrug off sun, rain and wind and look good doing it. With UV absorbers to reduce sun damage and mildewcides to keep mold and fungi at bay, General Finishes' Exterior 450 will reduce fading and greatly lengthen the life of any exterior wood. A water-based clear acrylic finish, it's ready to sand in only 1 hour, is low-odor and is easy to clean up. It's very flexible, so it resists the cracking and peeling caused by hot summers and cold winters. If you're looking for a durable finish for patio and deck furniture, garden furniture, pergolas, entrance doors and more, look no further than Exterior 450 Semi-Gloss. Quart or gallon. Also available in Gloss and Satin.

Features:
  • Cleanup: Warm, soapy water.
  • Dry Time: Ready to sand in 1 hour under ideal conditions (70°F, 70% humidity). Cooler temperatures and higher humidity will prolong drying time.
  • Application: Use a foam brush, paint pad applicator or spray gun.
  • Can be sprayed through compressed air, HVLP, airless or C.A.S. units.
  • Oil-based stains must be completey dry before using a water-based top coat. Wait a minimum of 48 hours before applying General Finishes Exterior 450.
(1) General Finishes Exterior 450 Varnish
More Information
Brand General Finishes
Weight 9.2000
Tech Spec
  • Dry Time at 75 Degrees: 30 minutes - 2 hours; Dry to Sanding Time: 1-2 hours
  • Suggested Application: Brush or Spray
  • Suggested Surface Prep: Clean and dry. Sand raw wood with 150 grit paper and sand 220 grit between coats.
  • Clean-up: Soap and Water
  • Shelf Life: 1 Year
  • Thinning: If necessary, thin with 10-20% water.
  • Suggested Stain: Can be used over most water base and solvent base stains. For ideal results use with General Finishes Exterior 450 Stains.
Finish Semi Gloss
Color Clear
Size Gallon, Quart
Use Exterior
4.8 / 5.0
12 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
9
3
0
0
0
Great Product
Applies beautifully. Very forgiving - for beginners like me. Quick drying.The semi-gloss finish, turned my teak patio table into a lovey piece of outdoor furniture. I would suggest using in a well ventilated area + use a mask or respirator.
July 9, 2019
Purchased
9 months ago
Woodworking Experience:
Beginner
Working great for me
I like the fastness of the dry time and the finish after three coats
June 6, 2018
Purchased
1 year ago
Woodworking Experience:
Intermediate
Wonderful product
This product appears to be wonderful but time will tell as it is on my front door exterior surface. It applied easily and looks great.
November 24, 2017
Purchased
over 2 years ago
Woodworking Experience:
Beginner
Quality
Amazing product. Rolled it with a foam brush on my patio cover gave it a sand with 320 and added one more coat and I have a super smooth finish.
Semi gloss finish gave it just enough sheen
Semi gloss finish gave it just enough sheen
July 2, 2017
Purchased
over 2 years ago
Woodworking Experience:
Intermediate
Excellent
Excellent product very pleased with it
October 28, 2016
Purchased
over 3 years ago
The General finishes Exterior 450 was the best product I ever bought. I sanded down a french door and tryed 3 different stains (spot tested) but was not getting any kind of good results.
The Exterior 450 was my last choice and it did the job. The wood was cedar and it came out great and my wife was happy.
I recomen that you read the label very carefully because it makes a world of difference for the finished product.

I will send a picture in the future.
October 13, 2016
Purchased
over 3 years ago
Woodworking Experience:
Intermediate
Finally! An excellent water based durable exterior finish!
A few years back, I cleaned out my parents’ house and was really surprised at the yellowing of the oil based finishes (one of the best available at the time) on my mom's old artwork projects. Many actually obscured the image below the finish. I design and build laser cut ornaments, signs, and other ornamental items. Since I like to think many of these will survive generations to become family heirlooms, I wanted a finish that would look good and hold up for many years without yellowing. My previous experiences with brand name, water based polyurethane finishes available from the big box stores had been at best, dismal. They never even looked good initially and self-destructed quickly even in moderate environments. General Finishes Exterior 450 was recommended and I have used nothing else since. The finish sprays on well (HPLV), is VERY forgiving (self-leveling what would have been ugly runs with other finishes), dries very quickly, and filters out UV rays that otherwise would brown out exotic woods such as Purpleheart and Padauk. When sprayed inside, odor is minimal (my shop is in our house but my wife has never even chased me outside to try to finish a project). Sand lightly (400 grit) between coats and the appearance goes from excellent to spectacular. A welcome sign I made 4 years ago hanging outside beside our front door looks the same as the day I made it (well, after you dust the pollen off this time of year). The laser cut star I designed this year weathered incredibly well even with the extensive edge cut Baltic Birch plywood surface area. I highly recommend it for ease of use, finish quality, and durability!
Welcome Sign
Purpleheart Christmas Ornament
Baltic Birch laser cut star
March 23, 2016
Purchased
over 5 years ago
Woodworking Experience:
Advanced
Bird House Friendly
I have used Exterior 450 on over 400 bird houses over the past 3 years. I use recycled cedar and the finish after 2 coats is amazing. The wood shows almost no weathering after 3 Texas summers, and the soap and water cleanup saves me lots o time, too! I just wish it would go on sale every once in a while.
March 2, 2016
Woodworking Experience:
Intermediate
Good finish
Goes on easily, doesn't separate in can and finish is very smooth.
March 1, 2018
Purchased
over 2 years ago
Woodworking Experience:
Intermediate
General finishes Exterior-450 water base semi-gloss finish
I used this finish for some cabinet work I did in our travel trailer.
I only wish the manufacturer of our trailer had used this product!
August 25, 2017
Purchased
over 2 years ago
Woodworking Experience:
Advanced
Start typing your question and we'll check if it was already asked and answered. Learn More
Browse 8 questions Browse 8 questions and 9 answers
Why did you choose this?
Rockler Store
I just built an exterior Patio table from white oak.
George B on Jun 5, 2018
450 IS A SUPERIOR EXT. TOP COAT
howard c on Jul 1, 2016
I just built an exterior Patio table from white oak.
George B on Jun 5, 2018
This tastes funny and gives me the runs
ANDRE V on Jan 9, 2017
450 IS A SUPERIOR EXT. TOP COAT
howard c on Jul 1, 2016
Have recently used this product. Love the quality and ease of use and beautiful results of EF finishes. This is a new product and I think it is exceptional.
Lona L on May 13, 2015
This tastes funny and gives me the runs
ANDRE V on Jan 9, 2017
Have recently used this product. Love the quality and ease of use and beautiful results of EF finishes. This is a new product and I think it is exceptional.
Lona L on May 13, 2015
What is the coverage of Exterior 450 Semi- Gloss, per can in the available sizes?
Rob F on Mar 31, 2016
Can it b used on interior projects ?
Philip M on Oct 10, 2017
BEST ANSWER: Yes, this can be used for interior applications
Is it suitable for use on a bathroom vanity and woodwork that will be exposed to high humidity from showers?
splinters on Nov 14, 2019
BEST ANSWER: I believe it is suitable. I used it to finish a shoe rack that has been sitting outside, in Seattle, for two years without any damage to the finish. The rack is protected from rain, but not from our humidity, so I believe that it will work well for interior woodwork in high humidity. I have no experience using it on wood that gets standing water.
Can I add water to the finish?
Erick L on Mar 23, 2016
BEST ANSWER: Yes. The thinning instructions on the can allow thinning 10%-20% with water. However, I have sprayed straight out of the can through HPLV and air brush without any problems. It does a very good job of self leveling the surface undiluted, but does even better lightly sanded with 400 grit between coats. I imagine that thinning will decrease the self leveling characteristics.
i would like any feedback from anybody that has used the gf450 flat waterbase on vertical smooth cedar shakes?
paul s on Jun 11, 2017
BEST ANSWER: No but have uses Satin, Gloss and Semi Gloss an pine and Cyprus and over the top of exterior paint to protect doors, etc.... Never found anything that would stand up to the sun until I used General. Stands up to UL wear better than anything i have ever used.
floor coverage for gallon of exterior 450 ?
Pieter D on Jun 1, 2017
BEST ANSWER: 400 to 600 square-foot per gallon pending absorption rate of surface
I would like to use the 450 flat on smooth cedar siding shakes. Anybody with some experience along these lines?
paul s on Jun 11, 2017
I used 4 coats of General Finishes Exterior 450 Satin on a picnic table over a gel stain. Sitting in the hot sun the surface is sticky. The shaded portions are not sticky at all. How can I resolve this?
Barry W on Aug 3, 2016
Prop 65 WarningWARNING: This product can expose you to Toluene, which is known to the State of California to cause birth defects or other reproductive harm. www.P65Warnings.ca.gov