Coatings and LEED EQ 4.2

There is much misunderstanding on what coatings will comply with LEED EQ 4.2

LEED EQ 4.2 for new construction for clear wood finishes applied to interior elements: do not exceed the VOC content limit established in south Coast Air Quality Management District (SCAQMD) Rule 1113, Architectural coatings, rules in effect on January 1, 2004.

·         Clear wood finishes: varnish 350 g/l; lacquer 550g/l

·         Sealers: sanding sealers 275 g/l

·         Stains 250:250 g/l

What are my coating and stain options?

Stains

Water based or 250 g/l voc stains are your only choice. Most coating manufactures are currently manufacturing water based stains so many options are available. Solvent based 250 g/l are more limited in availability as the options for available solvents to meet these restrictions are limited.

Clear Coats

There are several options available to the finisher when it comes to Top Coats and Sealers.  Water based, 550 g/l lacquers, 350 g/l conversion varnish and polyester coatings.

Water based Coatings

Water based coatings have made significant improvements in the last few years. Color and clarity of these coatings is now comparable with solvent based coatings. The availability of raw materials has increased and this has brought the price of these coatings more in line with their solvent based counterparts. The typical voc range of these coatings is 100-300 g/l. Most water based coatings use a solvent that is miscible with water to help with the coalescing of the resin system. These coatings have become easier to apply and make an excellent choice for on-site application due to their low odor.

550 g/l lacquers

There are many available low voc solvent based products on the market today, nitrocellulose lacquers, water white lacquers, pre-catalyzed and catalyzed lacquers can all be formulated to fall into this category. Depending on performance requirements using a 550 g/l solvent base coating is a good option as these coatings apply and perform similar to their higher voc counterparts that are currently being used in many finishing shops across the country.

350 g/l Conversion Varnish

Most Conversion varnishes even though they are formulated for higher solids are still not formulated for 350 g/l that the LEED requirement calls for. Your coating supplier will have to formulate a low voc conversion varnish to meet these criteria. These popular coatings used mainly in the Kitchen Cabinet industry make for high quality extremely durable architectural coatings, however if applied on site due to their potentially stronger odor can raise other issues. However the low voc formulated products tend to have a lower odor due to the available solvents making them a good choice for complying with LEED.

Polyesters

Polyesters are very high solids clear and pigmented coatings that easily comply with LEED EQ 4.2.  These multi-component coatings begin at 98% solids before application and after adding the other components apply at 77-84% solids making their voc at approximately 160 g/l.  Polyesters easily produce the “closed pore “look that are used in many high end applications and their durability is excellent. These coatings are best shop applied however using plural component application equipment these coatings could be applied on site.

Choosing a finish system that complies with LEED EQ 4.2 is only limited by performance requirements and on-site application restriction.  All of the coatings mentioned are available in clear and pigmented versions however stains on the other hand have a more limited offering and your coating supplier will have to work with you on developing a stain system that will comply with the 250 g/l whether water based or low voc solvent formula.

LEED EQ 4.2 for new construction can only receive its 1 point for interior paints and coatings applied on-site however many LEED projects are requiring all of the paints and coatings used in the project comply with EQ 4.2 you now know that you have many options available to you.