In January, when I wrote my post about Mask Science with the science behind masks, advantages and disadvantages of mask types, practical tests, tips for optimization and a short note on why and how we double mask, I still hoped that the vaccine might make masks redundant in everyday life, and that this could be my last mask post. Right now, it looks like thanks to Delta, masks will stay with us for a while (…), and as many people are looking to upgrade their masks these days, I’d like to explain our double masking with the Hybrid Cloth Mask (aka Luckhaus Mask) in detail.
Table of Contents
Introduction, and Reasons for Double Masking: How Double Masks can combine efficient Filtering and gapless Fit
Double Masking with the Hybrid Cloth Mask on top of N95, KN95 or FFP2 Masks, Surgical Masks and Filter Materials
Frequently Asked Questions, Tipps, Tricks and Hacks for Double Masking, Conditions of Use and Thanksgiving
Double Masking can combine efficient Filtering and gapless Fit
When in spring 2020, N95 and FFP2 / KN95 masks were in short supply even for medical professionals, so that they often had to make them last for weeks, I helped lots of doctors and nurses to sew masks based on my Hybrid Pattern as covers for their precious medical masks, and I was surprised how perfectly the Hybrid fitted on top of them!
With risk group in the family, we have to be particularly careful about protecting ourselves, and the usual FFP2 / KN95 masks unfortunately gape quite badly on all of us. Therefore, we’ve also started wearing Hybrid Masks as covers over our FFP2 / KN95 masks early on. Our top masks do not only reliably seal the FFP2 / KN95 masks gapless, which we consider of highest importance, but also protect them from getting dirty, so that they can be worn a little longer.
The Hybrid Mask is also very suitable as a top mask for bearded people, because when the side channels are tightly drawn, they press protruding cheek hair much closer to the face, which drastically reduces the usual “beard gaps”.
A very broad variety of Hybrid Mask sewing patterns I’ve created by request for special face shapes, needs and preferences (f.e. noses, beards, space, etc.), which can also be worn as top masks and eliminate (or at least offset) all sorts of issues with the fit of medical masks, can be found in a separate article about Customized Hybrid Mask.
If you are not (yet) sure if double masking may be a good solution for you, my post about Mask Science might help to make up your mind and possibly find other ways to solve your specific issues. There, I present the scientific principles behind masks, the problem with gaps, advantages and disadvantages of the mask types, some practical home tests for both fit and filter efficiency, and also a wide range of tips and tricks for the optimization of all sorts of masks.
Double Masking with Cloth Masks over FFP2 / KN95 Masks
Due to a high material density and increased breathing resistance, FFP2 / KN95 masks are particularly sensitive to gaps, i.e. the air passes through where it’s easiest. Therefore, even small gaps can reduce the filter efficiency of FFP2 / KN95 masks drastically. To ensure that FFP3 / N95 and FFP2 / KN95 masks are worn correctly and fit perfectly on the person, professional environments (e.g. hospital) annually carry out elaborate fit tests with their employees.
Unfortunately, it’s not possible to replicate such fit tests at home, but there are tests (e.g. whether the glasses fog up :)) which let you at least roughly determine how gaplessly a mask fits and whether there is a need for optimization.
FFP2 / KN95 masks are characterized by a very high filter efficiency, but also have increased breathing resistance. Cloth masks worn on top of them should therefore be very thin, so that gaps are closed, but breathing is not made even more difficult. Please test not only the fit of your mask combos in advance, but also whether you can breathe easily with both masks, f.e. when climbing stairs! If this doesn’t work well for you, please do not use a top mask.
In general, it is advised to wear FFP2 / KN95 masks for a maximum of 75 minutes at a time and then to rest for at least 30 minutes, and to never wear the masks for more than a total of 8 hours when re-using them.
The Hybrid Cloth Mask on top of FFP2 / KN95 Masks
The shape of the Hybrid Mask complements the usual coffee-filter-shaped type of FFP2 / KN95 masks surprisingly well, and even the angles match each other! Over the standard one-size FFP2 / KN95 mask, the Hybrid Cloth Mask in length L (print the pattern in 110%) and width M (print the template in 100%) fits perfectly on very most people.
In everyday life, we usually wear two-layer top masks, which I have sewn in combinations of NWPP (non-woven polypropylene), thin cotton (e.g. batiste) and / or light silk. Breathing with a double mask is of course a little harder than without, but we find it absolutely tolerable – and it is even possible to teach several hours per day with it!
The Hybrid Mask can also be sewn in a single layer, by adding 1-2 cm at top and bottom, folding this allowance twice to the inside and stitching it down, while leaving open 1-2 cm at the side of the top seam, for nose wire insertion.
Before donning the FFP2 / KN95 mask, the flat-folded top edge should be rolled around a finger, so that the wire won’t stand out as a peak over the nose. When the mask is on your face, the nose can be pulled down slightly, and if the mask is too large, the bottom edge can be folded inwards. For us, a full-width nose piece improves the fit of the Hybrid Mask, even when worn as a top mask, but for some others it fits better without a nose wire. I recommend testing both!
Double Masking with Cloth Masks over Surgical Masks
Surgical masks are made of very efficient filtering materials, but due to their loose fit, a lot of their initial filter efficiency gets lost. The filter efficiency can therefore be drastically increased when surgical masks are made to fit gapless, i.e. from less than 40% for a loosely fitting surgical mask to over 80% for a gaplessly fitting surgical mask.
If you would like to have more space behind your masks and / or hide the surgical mask as well as possible, you can simply knot the ties of the surgical mask on the sides, as close as possible to their base, and fold in the protruding material. Due to these knots, the surgical mask protrudes further forward, so that breathing becomes even easier.
The Hybrid Cloth Mask on top of Surgical Masks
To be worn over surgical masks, the Hybrid Cloth Mask can be customized into any individual size (my pattern is available in XXS to XXL, and there are also Customized Patterns for various shapes and needs such as glasses, noses, beards, kids, space, etc.!). The combo usually fits gaplessly, is easy to breathe in and reliably stays in place, and we actually find it more comfortable than wearing a loosely fitted surgical mask without a Hybrid Mask on top :)
We usually wear two-layer or three-layer top masks, which I have sewn in combinations of cotton, polycotton, NWPP (non-woven polypropylene), pellon and / or silk, over surgical masks. In contrast to FFP2 / KN95 top masks, I tend to make sure that the materials I use have decent filter properties, in order to further increase the filter efficiency. As with FFP2 / KN95 face masks, it is very important to test in advance whether you can breathe without any problems!
Double Masking with High Filtration Materials
As mentioned before, we have a medical mask mandate in Germany, and furthermore, we can’t buy high filtration materials such as Filti (at least as far as I know!), so we don’t really have a choice but to double with medical masks.
If you live in a place where non-medical masks are allowed and high filtration materials are available, you can not only either (a) sew the filter materials into your mask or (b) use them as a separate insert, but you can also (c) sew (or just staple!) your own filter masks from high filtration materials, which may be even safer than surgical masks.
Compared to filter inserts, double masking is far less fiddly, and bottom masks stay in place better than inserts. Sewn-in filters stay in place really well, but are impossible to seperate, so you can’t care for the two kinds of materials the way they need to be cared for. Ideally, fabrics should be washed, while filters can sometimes be reused, but should be disposed at the end of their pre-detemined lifespan. With seperate masks, you can still keep the cloth part.
The Hybrid Cloth Mask on top of Hybrid Instant Masks
In addition to the Hybrid Cloth Mask, I have created a simplified Hybrid Instant Masks (originally for non-sewers) that is based on the very same pattern and can be sewn (or even stapled!) extremely quick and easy. Those two masks fit gaplessly, comfortably, breathable and slip-free on top of each other, and complement each other perfectly!
Frequently Asked Questions, Tips and Tricks for Double Masking
These tipps and tricks do not only relate to one of the combos introduced above – the Hybrid Cloth Mask on top of N95, KN95 or FFP2 type of Masks, Surgical Masks or Homemade Filter Masks –, but to any type of double masks.
What’s the easiest way to don and tie double masks?
So far, all our FFP2 / KN95 and surgical masks have had extremely long ear loops. We either (a) add a slip knot to the extended ear loops, so that they can be used just like short ear loops and prevent the mask from slipping, or (b) attach the extended ear loops behind the head with the small hook, which is often included, a paper clip or a hair clip.
On top, we wear the Hybrid Mask either (a) with adjustable ear loops made of soft, flat elastics or, for longer wearing, (b) with extended ear loops that can be attached ar the back of the head together with those of the FFP2 / KN95 or surgical mask (see below), or (c) very long head ties made of jersey strips, also known as tshirt yarn. On me, head ties fit best when I cross them, so that the bottom tie sits above my hair bun and the top tie sits under the hair bun.
In less risky situations, where you have to don and doff masks more often, we treat both masks as one. To do this, we set the length of the ear loops of the top mask to the length of the ear loops of the bottom mask, pull the knot tight and down or into the channel, and nest the masks into each other. Now we slide a paper clip (if hair gets tangled, you can bend them open! :)) over both loops on the right side, until they sit safely in the large hole of the paper clip.
When donning the mask, we check that both masks are centered and that the reverse pleat of the top mask sits over the top edge of the bottom mask. Then, behind the head, we hook the paper clip into the two left straps. It doesn’t take any longer and is not more complicated than donning a single mask and, if necessary, can be done one-handed!
How do you carry and clean double masks, and do you reuse them?
We usually carry our masks readily doubled and folded in the middle, in small plastic bags that we wash regularly. If the masks are definitely not contaminated, dirty or wet after being worn, we will likely wear them again. After use, we put all our masks in paper bags, then wash the cloth masks in the laundry, and if the high filtering masks are still perfectly clean and dry, we might wear them again after 2-3 weeks of airing, and a maximum of 8 hours in total.
Can I double mask the other way, Filter Mask over Cloth Mask?
Of course you can, but you might end up corrupting the medical mask’s filter efficiency, so I highly recommend to wear the medical mask as close to your skin as your possibly can, and the cloth mask on top! Plus, when your medical mask stays clean (and it will rather get contaminated on the outside than on the inside), you can use it a little longer.
Doesn’t the CDC recommend to not use top masks over KN95s?
The CDC doesn’t recommend double masking with the KN95 type of masks in general, but doesn’t give reasons for that. As far as we could figure out, they might (a) assume KN95s to fit perfectly on everyone (which made us assume that they’re likely all 1.80 m / 6 ft and male, as that’s the usual standard for product testing :)) and (b) want to avoid people to put 5 layer homemade masks on top of high filtration masks, as this might result in serious breathing issues.
From a common sense perspective, when KN95s just don’t fit at all (and therefore, might loose most of their filter efficiency!), the best you can do is find a way to make them fit gapless – and if done responsibly, with a thin layer or two, top masks are the most reasonable option I know. But in case you can’t breathe well, please don’t double mask!
Can I avoid all the plastic waste from medical masks?
I don’t like that either, and I wish there was a way to keep me and my family safe without producing that much plastic waste! Unfortunately, the materials you can buy for sewing homemade masks just aren’t as effective at filtering, while medical masks are. With top masks, you can at least keep the disposables a little longer, and then safely reuse them.
Where can I find the printable pattern for the Hybrid Mask?
You can find my Hybrid Mask including instructions, pattern and downloads in a separate post, there’s also a picture tutorial, and if you’re looking for customizations (nose, chin, beard, space, etc.), there’s another separate post!
Can I possibly purchase the Hybrid Cloth mask from you?
Right now, I only sew for friends and family, because it seems more important to publish instructions and pattern of my Hybrid Cloth Mask, in order help others to help those in need – and besides my daily work, there’s no time for more than answering questions and continously updating German and English posts and instructions. But in the meantime, I’ve been lucky to find fabulous sewing partners, who offer professionally sewn, beautiful Hybrid Masks! ➔
This post corresponds to my level of knowledge by August 16th, 2021 and as usual, if there is any new information, it will be corrected accordingly. And I am always very happy to receive comments, questions, tips and new studies!
If you are curious now and would like to read more about Hybrid Cloth Mask Pattern, associated Pictorial Instructions, Instant Masks, Tying Techniques, etc., all links with pictures are available on my Mask Hub Page! ➔
Conditions of Use, Rights and Sharing
This post is more than welcome to be shared. Design, pattern and instructions of the hybrid mask are, however, protected by German copyright laws (© Iris Luckhaus | All rights reserved) and may only be used non-commercially. I’m always delighted to discover photos of hybrid masks with the tags @irisluckhaus and #luckhausmask! :)
For updates and further developments (which are sure to come!), please follow me on Facebook, Twitter, Instagram, Xing, LinkedIn, Pinterest or YouTube. If you’d like to share my pattern with your friends, feel free to use my posts!
I’m spending a lot of unpaid time on elaborating and explaining those instructions, helping the helpers to help. If you’d like to encourage this, I’d highly appreciate if you could buy me a little time via Paypal (firstname.lastname@example.org)!
If you’d like to use my instructions commercially (i.e. with the intention of making a profit), f.e. by selling masks sewn according to my pattern, please contact me and let me know more about your business, your location and your ideas!
Great thanks to my favorite mask testers Matthias Klesse, Angelika Luckhaus and Reinhard Luckhaus as well as to all the amazing makers (including various Facebook groups) for the instructive discussions, interesting studies, good questions, great enthusiasm and exciting tests, for reading and feeding this post and all the amazing encouragement!