The suggested use of support beams has proven very helpful indeed. Thanks much.

Left shift lets you place pieces without snapping to the frame, it disables the snap-to function.

Yes, red isn't good. There's a support system in the game. Blue is best, contact with the ground or a tree, for example, will give you blue level stability which means that piece will be fully supported. Green is good. Then you get three more levels of stability or support. Yellow, orange, and red (ruined). Red is bad, the piece will collapse if it's red.

Some higher tier materials have higher stability and let you build larger structures. I read that if you build stone up to nearly the maximum height, then build wood above that it can basically double your height limit.

From the Wiki:
A directly vertical pole of Wood or Stone can rise 16m off the ground before it cannot support anything above it. This is true for Wood wall, Wood wall half, Stone wall 1x1, Stone wall 2x1, Stone wall 4x2, Wood pole 1m, Wood pole 2m, Stone pillar.

A directly vertical Core wood Pole Logs can rise 24m off the ground before it cannot support anything above it. This is true for Log pole 4m and Log pole 2m.

A directly vertical Wood iron pole can rise up to 50m off the ground before it cannot support anything above it.

Trees, including those planted by the player, will effectively function as "the ground" for support purposes allowing for extremely high construction.

I have read that sometimes the colours don't always display properly while building but I've had very little trouble with it.

If you want some in game help just shoot me a friend request and I'll jump in with you for a bit.

Originally posted by Macdallan:

Left shift lets you place pieces without snapping to the frame, it disables the snap-to function.

Thanks. A bit of esoterica I didn't know that will really be useful

This is a bit outdated since a few things have changed since it was posted, but it still a good basic building guide:

https://www.ign.com/wikis/valheim/Building_Guide

It took me a while to get used to the building system, and some players end up being frustrated by it, but once you get used to it the system is actually pretty robust and not a difficult as it initially seems to be.

blue means that the piece is 'grounded', it has the best structural support. from there how well the piece is supported goes from shades of green to to yellow to orange to red. beams can be uses to increase support, as well as some environmental objects like trees. if a piece is not supported from a piece below it, it's color will show how much support it has... so if you have a floor piece that's blue and attach a wall to it the wall will be dark green. if you place another wall on top it will be a lighter shade green. if you put a roof on the 2nd wall it will be a lighter green and so on. if you kept extending roof pieces eventually they'll have too little support and will be a dark red and just break upon placing them, unless you add a support beam coming up from the ground. also if you went back to the first wall you built and removed it, everything above it would lose that support and fall apart.
pieces should snap together edge to edge without having to push shift or control. sometimes it helps to build yourself a scaffold to get a better view of the piece your snapping to.
one other thing, currently (and this may change in later updates) immediately after you initially place a piece it takes a moment to update the stabilities of it and the other pieces it attaches to, so if you're fast you can place pieces that normally wouldn't be able to be placed.

Good advice, hazelrah.

The build system does somewhat work like a real building would, you have to make sure things are stable otherwise it won't work.

You can frame the floor, roof, and walls with support beams before actually building a floor, roof, and walls. This can make it really easy to snap the walls, roof, and floors in place. Takes more resources but usually makes a stronger building, and it's usually less frustrating if you aren't used to the system.

Like I said, I've seen some pretty huge builds using just wood so the system is robust and you can do a lot with it once you get used to it.