Exterior Insulation and Finishing System (EIFS), Airborne Sound Transmission, and Roofing (Parts 5 & 9 of the NBC)
Exterior Insulation and Finishing System (EIFS), Airborne Sound Transmission, and Roofing (Parts 5 & 9 of the NBC) - Transcription
Slide 1
Hello, my name is Mihailo Mihailovic. I am a Technical Advisor here at Codes Canada.
I am pleased to give you an update on some of the changes that were made to Parts 5 and 9 of the 2015 National Building Code (NBC).
Slide 2
This presentation is part of a series of 13 presentations on the 2015 editions of Codes Canada.
Before I begin with the technical content of this presentation, I will speak briefly about the code development system.
It is important to note that the model Codes, which are developed by the Canadian Commission on Building and Fire Codes, must be adopted by provincial/territorial authorities to become law.
This may mean that Code requirements enacted by legislation within your province or territory might differ from what is presented here. Please check with your local authority.
Slide 3
It is also important to point out that the National Codes are not a federal regulation.
This means it is not NRC or Codes Canada that decides what goes into the Codes but you!
Codes Canada facilitates an open, transparent, consensus-based process to come up with improvements.
Over 400 committee members volunteer their time to decide on changes to the next Codes.
All committees are balanced between regulators, industry and public interest so that no single category can outvote the other two.
This process is shown on the slide:
- It typically starts with someone requesting a Code change.
- It continues with technical committees developing proposed changes.
- It involves a public review and the final approval by the Canadian Commission on Building and Fire Codes.
It's a simple process and it depends on your input.
Please go to the Codes Canada website and find out how you can:
- submit code change requests,
- participate in committees, or
- comment on proposed changes during our public reviews.
Slide 4
And before we start, here are some clarifications on the presentations themselves:
The presentations cover only the changes from 2010/2011 to 2015 Codes and not how to use or interpret the Codes in general.
The presentations contain only the significant changes - the details are in the handbook. Each presentation contains a reference to the relevant pages in the handbook.
The presentations stay strictly within the scope of the National Codes and do not cover provincial or territorial variations.
Slide 5
For this presentation, we will learn:
- how airborne sound is best measured between rooms,
- why there are a lot of new standards referenced for roofing, dampproofing and waterproofing materials, and
- how the new requirements for exterior insulation finish systems (EIFS) work.
Handbook pages 37-39 (Part 5) and 45-47 (Part 9)
Slide 6
Are you concerned about noisy neighbours?
The illustrations on the slide show the two main design scenarios for which airborne sound transmission requirements apply:
- walls between side-by-side units, and
- floors between stacked units.
The requirements for sound control between dwelling units in the 2010 NBC were based on sound going directly through the separating wall or floor. This is called sound transmission class or STC.
Unfortunately, the STC only represents part of what the occupant hears.
No wonder that so many of us complain about our neighbours sound system or the crying baby.
Slide 7
These drawings show the same assemblies, but illustrate that sound also travels through other paths.
These paths shown in dotted blue lines are called flanking paths or indirect paths.
Apparent sound transmission class or ASTC is a new concept that includes all paths.
And if you have ever lived or stayed in a condominium, you may know that sound from one room to the next isn't only transmitted directly through the wall, but also:
- through the floor, under the separating wall, and out of the floor into the receiving room, or
- into the floor and out of the separating wall.
The same goes for rooms one above another as shown in the picture on the right.
ASTC is the sum of all flanking sound transmission paths (indirect paths) and the direct sound transmission path.
ASTC better reflects what is actually heard by the occupant.
With the old method, designers would overdesign for the direct path only in an attempt to meet the Code's intent and occupant expectations.
In the 2015 NBC, the design and construction need to address both direct and indirect sound paths.
This new metric is in Parts 9 and 5 of the 2015 NBC.
Slide 8
This change makes ASTC address the performance of the complete assembly without having to overdesign.
The required level of performance has not been increased.
Three compliance paths were developed for Part 5 and Part 9:
- Measurements of the finished dwelling units and Part 9 as built without modifications.
- Design and calculation, which includes two methods:
- the detailed method, and
- the simplified method.
- Prescriptive method: The existing STC values in the sound tables still apply plus additional requirements to address flanking. The resulting construction is deemed to be equivalent to an ASTC 47 or better. No test or calculation is required.
Regardless of the building type, a designer can use any of the three methods described in the Code.
Slide 9
If you are looking to learn more, the NBC references the NRC Guide to Calculating Airborne Sound Transmission in Buildings.
The illustration shows the summary of the simplified calculation method for the assemblies you saw in the previous slides.
It is for a single wood stud wall with double gypsum board and resilient channels over I-joists floors.
The Guide provides sample illustrations, step by step explanations and simplified calculations for a number of assembly types, along with detailed calculations.
This Guide is available free of charge on the NRC website.
Slide 10
Or you can use an online software developed by NRC.
The NRC's acoustics researchers developed a tool called soundPATHS which models both direct and flanking sound transmission.
It calculates ASTC according to the design compliance path in the 2015 NBC.
This tool can help identify areas of overdesign and potential cost savings.
The tool allows the modeling of numerous construction types with more being added all the time.
This is a free tool and NRC has just posted a new version on its website.
Slide 11
Next, it's all about the “oofings”, roofing, dampproofing and waterproofing.
Slide 12
One thing that roofing, waterproofing and dampproofing materials have in common, apart from being black and sometimes goopy, is that the standards that govern these materials are often very old.
Many of the Canadian standards referenced for roofing, waterproofing, and dampproofing materials and their applications have been withdrawn by the organization that originally published them.
The standards that were not withdrawn were often outdated and sometimes even obsolete.
Normally, withdrawn standards are not a problem in the Code if they still satisfy the intent of the Code provisions.
But, in this case, contractors and designers were concerned with increased liability of not being able to buy Code compliant materials.
This also created a problem for building officials when they were trying to figure out if a particular material complied with the Code.
So what was done?
Added new standards - The 2015 NBC now references up-to-date American standards where they have been found to be acceptable.
Deleted obsolete standards - Some Canadian material standards were found to be obsolete and were deleted.
Kept acceptable outdated standards - When no acceptable replacements were found, the outdated Canadian material standards are still referenced in Part 9 because, even if outdated, they still reflected acceptable levels of performance.
This means that a lot of new roofing, dampproofing and waterproofing materials are now acceptable solutions in Part 9 and in Part 5.
In addition, the Section in Part 5 where these requirements are found was rewritten and restructured.
To support innovation and design flexibility, the 2015 NBC now has performance criteria for dampproofing only.
Slide 13
In terms of outdated installation standards, the approaches differ slightly for Part 5 and for Part 9.
In Part 5, the installation standards were deleted.
In Part 9, they were replaced with some key prescriptive Code requirements.
The 2015 NBC now better describes where dampproofing and waterproofing requirements apply.
Slide 14
The same approach was used for the roofing standards.
An additional change is that the standards for roofing have been reorganized in two tables by roofing types.
So all in all, a lot of new standards are referenced which will give designers and builders more options.
Slide 15
Now, let's look at what's new for EIFS.
Slide 16
The illustration on the left shows the typical build up of an EIFS assembly:
- backup wall,
- foam insulation,
- mesh laid into screed, and
- one or two finish coats very similar to stucco.
In the photo on the right, you see the end product on left hand side of the building façade.
As many of you may know, EIFS systems have had their problems over the years.
Old-style EIFS system were face-sealed systems.
So when small cracks occurred, water would get in but couldn't get out and this led to rot.
Part 9 didn't have prescriptive requirements for EIFS and the requirements for stucco were not applicable.
So for a Part 9 building, you could only use EIFS if it was to design the building envelope using Part 5, which requires the use of a professional.
In response, the EIFS industry supported the development of a set of standards that describe rainscreen EIFS, which has drainage capacity built-in allowing infiltrated water to escape.
Slide 17
As for Part 9 of the 2015 NBC, it:
- references three ULC standards dealing with materials, installation and design for EIFS, and
- imposes additional limitations on the rainscreen configurations for EIFS for high-moisture regions.
Slide 18
The following are additional requirements for rainscreen EIFS in Part 9.
The backside of the insulation of the EIFS system (here in light gray) must have grooves in it to allow drainage.
On the bottom right, you see the minimum requirements for this groove:
- the open area of the groove has to be at least 13% of the surface area of the insulation board, and
- it also has to have a minimum depth of 10 mm.
These will:
- reduce the likelihood of water bridging the gap, and
- allow the water to freely flow down the groove.
For this to happen, grooves of one panel have to connect to the grooves on the adjacent panels.
The size of the grooves can be verified by inspecting a single panel.
The intent is that the required drainage capacity be achieved across the entire system.
Of course, using the Part 5 design requirements is always an option.
Slide 19
Part 5 of the 2015 NBC only references the EIFS materials standard in the body of the Code, in addition to the general design procedure for cladding systems.
This approach allows flexibility in the designing of EIFS systems.
The Appendix to Part 5 includes:
- offers new guidance on design options and considerations,
- gives a lot of attention to the drainage cavity, and
- references the EIFS Practice Manual, which you can get free of charge from the EIFS Council of Canada website.
Slide 20
So, after all of this, what have we learnt?
ASTC accounts for flanking noise contributions through the wall/floor/ceiling systems and has a new calculation method.
The standards for roofing, dampproofing, and waterproofing have been updated, where possible.
There are many new acceptable materials and also new prescriptive requirements for installation in Part 9.
EIFS is now addressed prescriptively in Part 9 to ensure that the proper drainage path is installed in the cladding system.
And, by referencing the ULC standards, there are now clearer requirements for the proper design and installation of EIFS as a wall cladding.
Part 5 added a lot of guidance for designers.
Slide 21
I have covered a lot of information in today's presentation. The handbook is a useful resource if you want to review the topics from this presentation in more detail.
It covers the majority of technical changes that were implemented in the 2015 National Building Code, National Fire Code, National Plumbing Code and National Energy Code for Buildings.
The handbook can be purchased on NRC's virtual store as a downloadable PDF or as a hard copy.
Slide 22
Contact Information
| Autre titre | Exterior Insulation and Finishing System (EIFS), Airborne Sound Transmission, and Roofing (Parts 5 and 9 of the National Building Code of Canada: 2015) |
|---|---|
| Téléchargement | |
| DOI | Trouver le DOI : https://doi.org/10.4224/40002096 |
| Auteur | Rechercher : 1; Rechercher : 1 |
| Orateur | Rechercher : Mihailovic, Mihailo1 |
| Affiliation |
|
| Format | Vidéo, Object d'apprentissage |
| Sujet | Codes et guides; Transmission acoustique et insonorisation; construction; bâtiment; NRCCode |
| Date de publication | 2015 |
| Maison d’édition | National Research Council of Canada |
| Publication connexe | |
| Langue | anglais |
| Exporter la notice | Exporter en format RIS |
| Signaler une correction | Signaler une correction (s'ouvre dans un nouvel onglet) |
| Identificateur de l’enregistrement | 6218edc9-d3ae-41b3-b868-1c2f0f03bd61 |
| Enregistrement créé | 2021-05-04 |
| Enregistrement modifié | 2022-06-21 |
- Date de modification :