diff --git a/lib/any.js b/lib/any.js
index addfe8be7..6537ff496 100644
--- a/lib/any.js
+++ b/lib/any.js
@@ -218,8 +218,14 @@ module.exports = internals.Any = class {
 
     raw(isRaw) {
 
+        const value = isRaw === undefined ? true : isRaw;
+
+        if (this._flags.raw === value) {
+            return this;
+        }
+
         const obj = this.clone();
-        obj._flags.raw = isRaw === undefined ? true : isRaw;
+        obj._flags.raw = value;
         return obj;
     }
 
@@ -270,6 +276,10 @@ module.exports = internals.Any = class {
 
     required() {
 
+        if (this._flags.presence === 'required') {
+            return this;
+        }
+
         const obj = this.clone();
         obj._flags.presence = 'required';
         return obj;
@@ -277,6 +287,10 @@ module.exports = internals.Any = class {
 
     optional() {
 
+        if (this._flags.presence === 'optional') {
+            return this;
+        }
+
         const obj = this.clone();
         obj._flags.presence = 'optional';
         return obj;
@@ -285,6 +299,10 @@ module.exports = internals.Any = class {
 
     forbidden() {
 
+        if (this._flags.presence === 'forbidden') {
+            return this;
+        }
+
         const obj = this.clone();
         obj._flags.presence = 'forbidden';
         return obj;
@@ -293,6 +311,10 @@ module.exports = internals.Any = class {
 
     strip() {
 
+        if (this._flags.strip) {
+            return this;
+        }
+
         const obj = this.clone();
         obj._flags.strip = true;
         return obj;
diff --git a/lib/array.js b/lib/array.js
index 4ebfbfb1f..ae83da2c0 100644
--- a/lib/array.js
+++ b/lib/array.js
@@ -529,15 +529,27 @@ internals.Array = class extends Any {
 
     sparse(enabled) {
 
+        const value = enabled === undefined ? true : !!enabled;
+
+        if (this._flags.sparse === value) {
+            return this;
+        }
+
         const obj = this.clone();
-        obj._flags.sparse = enabled === undefined ? true : !!enabled;
+        obj._flags.sparse = value;
         return obj;
     }
 
     single(enabled) {
 
+        const value = enabled === undefined ? true : !!enabled;
+
+        if (this._flags.single === value) {
+            return this;
+        }
+
         const obj = this.clone();
-        obj._flags.single = enabled === undefined ? true : !!enabled;
+        obj._flags.single = value;
         return obj;
     }
 
diff --git a/lib/binary.js b/lib/binary.js
index 6d9851f55..d064fd657 100644
--- a/lib/binary.js
+++ b/lib/binary.js
@@ -43,6 +43,10 @@ internals.Binary = class extends Any {
 
         Hoek.assert(Buffer.isEncoding(encoding), 'Invalid encoding:', encoding);
 
+        if (this._flags.encoding === encoding) {
+            return this;
+        }
+
         const obj = this.clone();
         obj._flags.encoding = encoding;
         return obj;
diff --git a/lib/boolean.js b/lib/boolean.js
index 8bc02bb13..ae34259d1 100644
--- a/lib/boolean.js
+++ b/lib/boolean.js
@@ -76,13 +76,13 @@ internals.Boolean = class extends Any {
 
         const insensitive = enabled === undefined ? true : !!enabled;
 
-        if (insensitive !== this._flags.insensitive) {
-            const obj = this.clone();
-            obj._flags.insensitive = insensitive;
-            return obj;
+        if (this._flags.insensitive === insensitive) {
+            return this;
         }
 
-        return this;
+        const obj = this.clone();
+        obj._flags.insensitive = insensitive;
+        return obj;
     }
 
     describe() {
diff --git a/lib/date.js b/lib/date.js
index 53f00b425..e5ad56a06 100644
--- a/lib/date.js
+++ b/lib/date.js
@@ -97,6 +97,10 @@ internals.Date = class extends Any {
 
     iso() {
 
+        if (this._flags.format === internals.isoDate) {
+            return this;
+        }
+
         const obj = this.clone();
         obj._flags.format = internals.isoDate;
         return obj;
@@ -109,6 +113,10 @@ internals.Date = class extends Any {
         const allowed = ['javascript', 'unix'];
         Hoek.assert(allowed.indexOf(type) !== -1, '"type" must be one of "' + allowed.join('", "') + '"');
 
+        if (this._flags.timestamp === type) {
+            return this;
+        }
+
         const obj = this.clone();
         obj._flags.timestamp = type;
         obj._flags.multiplier = type === 'unix' ? 1000 : 1;
diff --git a/lib/object.js b/lib/object.js
index 24607d21c..864734a00 100644
--- a/lib/object.js
+++ b/lib/object.js
@@ -325,8 +325,14 @@ internals.Object = class extends Any {
 
     unknown(allow) {
 
+        const value = allow !== false;
+
+        if (this._flags.allowUnknown === value) {
+            return this;
+        }
+
         const obj = this.clone();
-        obj._flags.allowUnknown = (allow !== false);
+        obj._flags.allowUnknown = value;
         return obj;
     }
 
diff --git a/lib/string.js b/lib/string.js
index b7a526478..51995da60 100644
--- a/lib/string.js
+++ b/lib/string.js
@@ -67,6 +67,10 @@ internals.String = class extends Any {
 
     insensitive() {
 
+        if (this._flags.insensitive) {
+            return this;
+        }
+
         const obj = this.clone();
         obj._flags.insensitive = true;
         return obj;
@@ -510,8 +514,14 @@ internals.String = class extends Any {
 
     truncate(enabled) {
 
+        const value = enabled === undefined ? true : !!enabled;
+
+        if (this._flags.truncate === value) {
+            return this;
+        }
+
         const obj = this.clone();
-        obj._flags.truncate = enabled === undefined ? true : !!enabled;
+        obj._flags.truncate = value;
         return obj;
     }
 
diff --git a/test/any.js b/test/any.js
index 6ab0dc0f5..4d6bd6471 100644
--- a/test/any.js
+++ b/test/any.js
@@ -265,6 +265,13 @@ describe('any', () => {
 
             done();
         });
+
+        it('avoids unnecessary cloning when called twice', (done) => {
+
+            const schema = Joi.any().raw();
+            expect(schema.raw()).to.shallow.equal(schema);
+            done();
+        });
     });
 
     describe('default()', () => {
@@ -773,6 +780,16 @@ describe('any', () => {
         });
     });
 
+    describe('required', () => {
+
+        it('avoids unnecessary cloning when called twice', (done) => {
+
+            const schema = Joi.any().required();
+            expect(schema.required()).to.shallow.equal(schema);
+            done();
+        });
+    });
+
     describe('optional()', () => {
 
         it('validates optional with default required', (done) => {
@@ -794,6 +811,13 @@ describe('any', () => {
                 [{ b: 5 }, false, null, 'child "a" fails because ["a" is required]']
             ], done);
         });
+
+        it('avoids unnecessary cloning when called twice', (done) => {
+
+            const schema = Joi.any().optional();
+            expect(schema.optional()).to.shallow.equal(schema);
+            done();
+        });
     });
 
     describe('forbidden()', () => {
@@ -814,6 +838,13 @@ describe('any', () => {
                 [{ b: null }, false, null, 'child "b" fails because ["b" is not allowed]']
             ], done);
         });
+
+        it('avoids unnecessary cloning when called twice', (done) => {
+
+            const schema = Joi.any().forbidden();
+            expect(schema.forbidden()).to.shallow.equal(schema);
+            done();
+        });
     });
 
     describe('strip()', () => {
@@ -841,6 +872,13 @@ describe('any', () => {
                 done();
             });
         });
+
+        it('avoids unnecessary cloning when called twice', (done) => {
+
+            const schema = Joi.any().strip();
+            expect(schema.strip()).to.shallow.equal(schema);
+            done();
+        });
     });
 
     describe('description()', () => {
diff --git a/test/array.js b/test/array.js
index 4f81e9bab..78de025fe 100644
--- a/test/array.js
+++ b/test/array.js
@@ -1145,6 +1145,13 @@ describe('array', () => {
             });
             done();
         });
+
+        it('avoids unnecessary cloning when called twice', (done) => {
+
+            const schema = Joi.array().sparse();
+            expect(schema.sparse()).to.shallow.equal(schema);
+            done();
+        });
     });
 
     describe('single()', () => {
@@ -1223,6 +1230,13 @@ describe('array', () => {
             });
             done();
         });
+
+        it('avoids unnecessary cloning when called twice', (done) => {
+
+            const schema = Joi.array().single();
+            expect(schema.single()).to.shallow.equal(schema);
+            done();
+        });
     });
 
     describe('options()', () => {
diff --git a/test/binary.js b/test/binary.js
index e8fa99f26..6d733ebd2 100644
--- a/test/binary.js
+++ b/test/binary.js
@@ -105,6 +105,13 @@ describe('binary', () => {
             }).to.throw('Invalid encoding: base6');
             done();
         });
+
+        it('avoids unnecessary cloning when called twice', (done) => {
+
+            const schema = Joi.binary().encoding('base64');
+            expect(schema.encoding('base64')).to.shallow.equal(schema);
+            done();
+        });
     });
 
     describe('min()', () => {
diff --git a/test/date.js b/test/date.js
index d48e18063..aa8b2500f 100644
--- a/test/date.js
+++ b/test/date.js
@@ -300,6 +300,13 @@ describe('date', () => {
 
         describe('iso()', () => {
 
+            it('avoids unnecessary cloning when called twice', (done) => {
+
+                const schema = Joi.date().iso();
+                expect(schema.iso()).to.shallow.equal(schema);
+                done();
+            });
+
             it('validates isoDate', (done) => {
 
                 Helper.validate(Joi.date().iso(), [
@@ -363,6 +370,13 @@ describe('date', () => {
 
         describe('timestamp()', () => {
 
+            it('avoids unnecessary cloning when called twice', (done) => {
+
+                const schema = Joi.date().timestamp('unix');
+                expect(schema.timestamp('unix')).to.shallow.equal(schema);
+                done();
+            });
+
             it('validates javascript timestamp', (done) => {
 
                 const now = new Date();
diff --git a/test/object.js b/test/object.js
index 24edfbb74..cbb9b05eb 100644
--- a/test/object.js
+++ b/test/object.js
@@ -558,6 +558,13 @@ describe('object', () => {
 
     describe('unknown()', () => {
 
+        it('avoids unnecessary cloning when called twice', (done) => {
+
+            const schema = Joi.object().unknown();
+            expect(schema.unknown()).to.shallow.equal(schema);
+            done();
+        });
+
         it('allows local unknown without applying to children', (done) => {
 
             const schema = Joi.object({
diff --git a/test/string.js b/test/string.js
index bd0d2e892..b61055401 100644
--- a/test/string.js
+++ b/test/string.js
@@ -52,6 +52,16 @@ describe('string', () => {
         ], done);
     });
 
+    describe('insensitive', () => {
+
+        it('avoids unnecessary cloning when called twice', (done) => {
+
+            const schema = Joi.string().insensitive();
+            expect(schema.insensitive()).to.shallow.equal(schema);
+            done();
+        });
+    });
+
     describe('valid()', () => {
 
         it('validates case sensitive values', (done) => {
@@ -1995,6 +2005,13 @@ describe('string', () => {
 
     describe('truncate()', () => {
 
+        it('avoids unnecessary cloning when called twice', (done) => {
+
+            const schema = Joi.string().truncate();
+            expect(schema.truncate()).to.shallow.equal(schema);
+            done();
+        });
+
         it('switches the truncate flag', (done) => {
 
             const schema = Joi.string().truncate();