Square in a Square Variation Quilt Block (Big 20″ Block!)

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This beginner-friendly 20″ quilt block looks more complicated than it is!

The quilt block starts with a small square in a square block and then gets bigger by adding a simple strip set element that can be a real trick of the eye depending on your fabric choices.

20 inch quilt block

This block is part of a series of large 20″ quilt blocks I’ve been making that can be used to make quick and easy beginner quilts or combined as part of the Big Blocks Quilt Along where I put three of these large blocks together into one quilt top.

You can sign up to the quilt along (even if you are reading this in the future!) here:

BIG BLOCKS QUILT ALONG SIGN UP

Fabric Requirements: Square in a Square Big Block

fabric cut for quilt block
Photo: Scrap Fabric Love
  • (1) 4.5″ Square
  • (4) 2.5″ Squares (you may want to match these to your strips but that is optional- see instructions below)
  • (2) 2.5″ x 34″ Strips (I used WOF strips and had a bit left over)
  • (4) 8.5″ Squares

If you would like to achieve the look in your block of your strips leading into your central square with alternating colors, then you need to match 2 of your 2.5″ squares to one of your long strips and 2 to the other strip.

Note: This is optional and if it is too fussy for you, can use different colors or all the same color for your 2.5″ squares and strips.

If you use an Accuquilt Cutter the dies relating to this block are these:

Step 1: Square in a Square Center Block

The very middle of this quilt block is a 4.5″ square in a square quilt block.

using a fabric pencil
Photo: Scrap Fabric Love

To make this draw a diagonal line from one corner to another on the wrong side of all four of your 2.5″ squares.

square in a square quilt block
Photo: Scrap Fabric Love

Next place two of your 2.5″ squares right sides to right sides with your 4.5″ square lining up the squares on opposite corners – if you are looking to match your strips and corners as pictured above make sure these 2.5″ squares are the same fabric.

square in a square quilt block
Photo: Scrap Fabric Love

Sew along your drawn line and trim away the excess corners with a 1/4″ seam allowance.

ironing square in a square
Photo: Scrap Fabric Love

Press your corners open and then repeat with the remaining two squares on the opposite corners of the 4.5″ square.

square in a square tutorial
Photo: Scrap Fabric Love
square in a square quilt block tutorial
Photo: Scrap Fabric Love

See photos and video tutorial (at the end of the post) if you aren’t sure what I mean!

square in a square quilt block tutorial
Photo: Scrap Fabric Love
square in a square quilt block
Photo: Scrap Fabric Love

Finally, trim this unit making sure it still measures 4.5″ square.

Step 2: Make your Strip Set

Sew your (2) 2.5″ x 34″ strips together right sides to right sides with a 1/4″ seam allowance.

fabric strip set
Photo: Scrap Fabric Love

I pressed my seams open but you can press however you prefer.

strip set units
Photo: Scrap Fabric Love

Next cut your strip set into (4) 8.5″ long units.

strip set units
Photo: Scrap Fabric Love

Step 3: Sew your units into a 9-patch

Lay out your block like a 9 patch with the (4) 8.5″ squares at each corner, the square in a square block in the center, and the strip sets in between.

big quilt block
Photo: Scrap Fabric Love
quilt block layout
Photo: Scrap Fabric Love

If you are looking to match the corners of your square in a square block with your strip set units make sure to rotate them so that the color of the strip aligns with the color of the corner unit it is touching. See photos and video below if you don’t understand.

quilt block construction
Photo: Scrap Fabric Love

Next, sew your units together in rows of 3 and finally sew the rows together to complete the block.

chain pieced quit block units
Photo: Scrap Fabric Love

Make sure to watch how your seams are nesting when you go to join the strip units to the adjoining units.

Finally trim your block down to 20″ square!

Finished Quilt Block

I only made one of these blocks as it is destined to be the centre block in my Big Blocks Quilt Along quilt where I am combining three big quilt block designs together.

Below my finished block photos you will see some mock-ups of how more than one of these blocks would look like in a quilt as well as a guide for how many blocks you will need.

big quilt block
Photo: Scrap Fabric Love
20 inch quilt block
Photo: Scrap Fabric Love

How many Blocks do I Need?

The great thing about big blocks like this is that you don’t need that many to start making a sizeable quilt.

Below are some examples of quilt sizes and how many blocks you will need. These measurements don’t include optional sashing and borders that would increase the size of your quilt.

  • Baby Quilt (39″ x 39″) = 4 Blocks.
  • Twin Quilt (39″ x 78″) = 8 Blocks
  • Lap Size/Throw Size (58.5″ x 58.5″) = 9 Blocks
  • Double Quilt (58.5″ x 78″) = 12 Blocks
  • Queen Size/King Size (78″ x 97.5″) = 20 Blocks

Below are examples of how different this block can look in different colorways as well as with and without sashing. The final image is a 4 block baby quilt where you can really see how the placement of the colors makes it look totally different!

quilt top layout
Photo: Scrap Fabric Love

The photo above and below are both 9 Block Lap Quilt layouts but look how different they look in the different colors!

black and white quilt layout
Photo: Scrap Fabric Love

Below is the same quilt as above but with the addition of sashing and borders.

quilt layout with border and sashing
Photo: Scrap Fabric Love
baby quilt layout
Photo: Scrap Fabric Love

I hope you can see from these examples how much fun you can have with this block!

Square in a Square Variation Big Block Video Tutorial

If you are a visual learner you might prefer the video tutorial for this post. If for any reason it doesn’t play below you can find it here.

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